Bayden Wood

A comparison of methods for detection of phosphate limitation in microalgae

Publisher: Springer Science and Business Media LLC

Date: 03-2001

DOI: 10.1007/PL00001342

Monitoring the reversible B to A-like transition of DNA in eukaryotic cells using Fourier transform infrared spectroscopy

Publisher: Oxford University Press (OUP)

Date: 28-03-2011

DOI: 10.1093/NAR/GKR175

Empirical study on the effects of acquisition parameters for FTIR hyperspectral imaging of brain tissue

Publisher: Royal Society of Chemistry (RSC)

Date: 2020

DOI: 10.1039/C9AY01200A

Abstract: Fourier transform infrared (FTIR) spectroscopic imaging is a powerful technique for molecular imaging of pathologies associated with the nervous systems including multiple sclerosis research.

Detection and Quantification of <em>Plasmodium falciparum</em> in Aqueous Red Blood Cells by Attenuated Total Reflection Infrared Spectroscopy and Multivariate Data Analysis

Publisher: MyJove Corporation

Date: 02-11-2018

DOI: 10.3791/56797

Abstract: We demonstrate a method of quantification and detection of parasites in aqueous red blood cells (RBCs) by using a simple benchtop Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectrometer in conjunction with Multivariate Data Analysis (MVDA). 3D7 P. falciparum were cultured to 10% parasitemia ring stage parasites and used to spike fresh donor isolated RBCs to create a dilution series between 0-1%. 10 µL of each s le were placed onto the center of the ATR diamond window to acquire the spectrum. The s le data was treated to improve the signal to noise ratio and to remove the contribution of water, and then the second derivative was applied to resolve spectral features. The data were then analyzed using two types of MVDA: first Principal Component Analysis (PCA) to determine any outliers and then Partial Least Squares Regression (PLS-R) to build the quantification model.

Importance of tissue preparation methods in FTIR micro-spectroscopical analysis of biological tissues: 'Traps for new users'

Publisher: Public Library of Science (PLoS)

Date: 24-02-2015

DOI: 10.1371/JOURNAL.PONE.0116491

Fourier transform infrared (FTIR) spectral mapping of the cervical transformation zone, and dysplastic squamous epithelium

Publisher: Elsevier BV

Date: 04-2004

DOI: 10.1016/J.YGYNO.2003.12.028

Detection and Quantification of Early-Stage Malaria Parasites in Laboratory Infected Erythrocytes by Attenuated Total Reflectance Infrared Spectroscopy and Multivariate Analysis

Publisher: American Chemical Society (ACS)

Date: 17-04-2014

DOI: 10.1021/AC500199X

Direct Determination of Metal Complexes’ Interaction with DNA by Atomic Telemetry and Multiscale Molecular Dynamics

Publisher: American Chemical Society (ACS)

Date: 03-02-2017

DOI: 10.1021/ACS.JPCLETT.7B00070

Abstract: The lack of molecular mechanistic understanding of the interaction between metal complexes and biomolecules h ers their potential medical use. Herein we present a robust procedure combining resonant X-ray emission spectroscopy and multiscale molecular dynamics simulations, which allows for straightforward elucidation of the precise interaction mechanism at the atomic level. The report unveils an unforeseen hydrolysis process and DNA binding of [Pt{N(p-HC

Screening of Wolbachia Endosymbiont Infection in Aedes aegypti Mosquitoes Using Attenuated Total Reflection Mid-Infrared Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 08-04-2017

DOI: 10.1021/ACS.ANALCHEM.6B04827

Abstract: Dengue fever is the most common mosquito transmitted viral infection afflicting humans, estimated to generate around 390 million infections each year in over 100 countries. The introduction of the endosymbiotic bacterium Wolbachia into Aedes aegypti mosquitoes has the potential to greatly reduce the public health burden of the disease. This approach requires extensive polymerase chain reaction (PCR) testing of the Wolbachia-infection status of mosquitoes in areas where Wolbachia-A. aegypti are released. Here, we report the first ex le of small organism mid-infrared spectroscopy where we have applied attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectroscopy and multivariate modeling methods to determine sex, age, and the presence of Wolbachia (wMel strain) in laboratory mosquitoes and sex and age in field mosquitoes. The prediction errors using partial least squares discriminant analysis (PLS-DA) discrimination models for laboratory studies on independent test sets ranged from 0 to 3% for age and sex grading and 3% to 5% for Wolbachia infection diagnosis using dry mosquito abdomens while field study results using an artificial neural network yielded a 10% error. The application of FT-IR analysis is inexpensive, easy to use, and portable and shows significant potential to replace the reliance on more expensive and laborious PCR assays.

Infrared Based Saliva Screening Test for COVID‐19

Publisher: Wiley

Date: 29-06-2021

DOI: 10.1002/ANGE.202104453

Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has resulted in an unprecedented need for diagnostic testing that is critical in controlling the spread of COVID‐19. We propose a portable infrared spectrometer with purpose‐built transflection accessory for rapid point‐of‐care detection of COVID‐19 markers in saliva. Initially, purified virion particles were characterized with Raman spectroscopy, synchrotron infrared (IR) and AFM‐IR. A data set comprising 171 transflection infrared spectra from 29 subjects testing positive for SARS‐CoV‐2 by RT‐qPCR and 28 testing negative, was modeled using Monte Carlo Double Cross Validation with 50 randomized test and model sets. The testing sensitivity was 93 % (27/29) with a specificity of 82 % (23/28) that included positive s les on the limit of detection for RT‐qPCR. Herein, we demonstrate a proof‐of‐concept high throughput infrared COVID‐19 test that is rapid, inexpensive, portable and utilizes s le self‐collection thus minimizing the risk to healthcare workers and ideally suited to mass screening.

Fatty acid distribution and polymorphism in solid lipid particles of milkfat and long chain omega-3 fatty acids

Publisher: Elsevier BV

Date: 07-2022

DOI: 10.1016/J.FOODCHEM.2022.132245

Abstract: Saturated fatty acid-containing lipids, such as milkfat, may protect long chain polyunsaturated fatty acids in fish oil when blended together into solid lipid particles (SLPs). One of the main challenges of SLPs is structural polymorphism, which can lead to expulsion of the protected component during prolonged storage. To investigate this phenomenon, the change in thermal and crystalline behaviours, and fatty acid distribution, were analysed in SLPs of fish oil and milkfat during storage at different temperatures for up to 28 days. X-ray diffraction analysis showed changes in molten and crystalline states occurred even at -22 °C. Room temperature (21 °C) storage led to more than 45% molten state but SLPs retained their initial shape. Confocal Raman Spectroscopy of the SLPs showed the distribution of fatty acids was not uniform, with 10 μm outermost layer of predominantly saturated fatty acids likely responsible for the intact SLP shape and stability of the core.

Fourier Transform Infrared Spectroscopy as a Method for Monitoring the Molecular Dynamics of Lymphocyte Activation

Publisher: SAGE Publications

Date: 03-2000

DOI: 10.1366/0003702001949627

Abstract: In this paper we report the application of Fourier transform infrared (FT-IR) microspectroscopy to monitor the molecular dynamics of lymphocyte activation. Infrared spectra of lymphocytes stimulated with the mitogen phytohaemagglutinin-L show spectral features 15 min after initial stimulation that are not apparent in resting lymphocytes. By analyzing the second-order derivatives of the raw spectra and applying principal components analysis (PCA), we conclude that the major spectral changes observed in the first hour result from an increase in overall RNA synthesis. Bands characteristic of RNA at 1244, 1080, 1050, 970, 1160, and 1120 cm −1 appear progressively more intense over time in the spectra of activated lymphocytes. The magnitude of these changes increases over time as the cell differentiates into a blast cell. The sensitivity of infrared spectroscopy to RNA moieties and the rapidity of the technique suggest a possible future role for FT-IR spectroscopy in histocompatibility testing.

Visualization and characterisation of defined hair follicle compartments by Fourier transform infrared (FTIR) imaging without labelling

Publisher: Elsevier BV

Date: 09-2011

DOI: 10.1016/J.JDERMSCI.2011.05.002

Abstract: To visualise and characterise skin architecture, the tissue usually has to be destroyed and labelled. The use of Fourier transform infrared (FTIR) spectroscopy as a label-free, minimally s le destructive method to define hair follicular structure has been explored and demonstrated in this paper. Human scalp skin cryosections were imaged using FTIR microscopy and the data was subsequently analysed with N-FINDR spectral unmixing algorithm. This resulted in an excellent distinction of known hair follicle tissue layers, which could be discerned based on their molecular structure. The development of a minimally s le-destructive, label-free spectroscopy based technique that can differentiate layers of cells in the dermal papilla and connective tissue sheath in the mesenchyme of the hair follicle paves the way forward to identifying spectral markers important in wound healing and stem cell therapies.

Fourier Transform Infrared Imaging and Unsupervised Hierarchical Clustering Applied to Cervical Biopsies

Publisher: CSIRO Publishing

Date: 2004

DOI: 10.1071/CH04137

Abstract: FTIR images of cervical tissue from patient biopsies were processed with an unsupervised hierarchical clustering algorithm and compared with hematoxylin- and eosin-stained adjacent sections. Anatomical and potential histopathological features were clearly resolved in the resultant cluster maps. The mean extracted spectra assigned to each cluster indicate that the major spectral differences between the different cells in tissue predictably occur in the amide I region (1700–1570 cm−1) and the phosphodiester/glycogen region (1200–1000 cm−1). FTIR imaging in which a focal plane array mercury–cadmium–telluride detector and unsupervised hierarchical clustering is used shows potential as a rapid, non-subjective diagnostic tool in cervical pathology.

Intracellular investigation on the differential effects of 4 polyphenols on MCF-7 breast cancer cells by Raman imaging

Publisher: Royal Society of Chemistry (RSC)

Date: 2018

DOI: 10.1039/C7AN01460K

Abstract: Nucleus evidenced from Raman I 1235 / I 2844 in breast cancer MCF-7 live cells.

Probing the action of a novel anti-leukaemic drug therapy at the single cell level using modern vibrational spectroscopy techniques

Publisher: Springer Science and Business Media LLC

Date: 06-2017

DOI: 10.1038/S41598-017-02069-5

Abstract: Acute myeloid leukaemia (AML) is a life threatening cancer for which there is an urgent clinical need for novel therapeutic approaches. A redeployed drug combination of bezafibrate and medroxyprogesterone acetate (BaP) has shown anti-leukaemic activity in vitro and in vivo . Elucidation of the BaP mechanism of action is required in order to understand how to maximise the clinical benefit. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Synchrotron radiation FTIR (S-FTIR) and Raman microspectroscopy are powerful complementary techniques which were employed to probe the biochemical composition of two AML cell lines in the presence and absence of BaP. Analysis was performed on single living cells along with dehydrated and fixed cells to provide a large and detailed data set. A consideration of the main spectral differences in conjunction with multivariate statistical analysis reveals a significant change to the cellular lipid composition with drug treatment furthermore, this response is not caused by cell apoptosis. No change to the DNA of either cell line was observed suggesting this combination therapy primarily targets lipid biosynthesis or effects bioactive lipids that activate specific signalling pathways.

Disposable Coverslip for Rapid Throughput Screening of Malaria Using Attenuated Total Reflection Spectroscopy

Publisher: SAGE Publications

Date: 06-05-2021

DOI: 10.1177/00037028211012722

Abstract: Malaria is considered to be one of the most catastrophic health issues in the whole world. Vibrational spectroscopy is a rapid, robust, label-free, inexpensive, highly sensitive, nonperturbative, and nondestructive technique with high diagnostic potential for the early detection of disease agents. In particular, the fingerprinting capability of attenuated total reflection spectroscopy is promising as a point-of-care diagnostic tool in resource-limited areas. However, improvements are required to expedite the measurements of biofluids, including the drying procedure and subsequent cleaning of the internal reflection element to enable high throughput successive measurements. As an alternative, we propose using an inexpensive coverslip to reduce the s le preparation time by enabling multiple s les to be collectively dried together under the same temperature and conditions. In conjunction with partial least squares regression, attenuated total reflection spectroscopy was able to detect and quantify the parasitemia with root mean square error of cross-validation and R 2 values of 0.177 and 0.985, respectively. Here, we characterize an inexpensive, disposable coverslip for the high throughput screening of malaria parasitic infections and thus demonstrate an alternative approach to direct deposition of the s le onto the internal reflection element.

Synchrotron macro ATR-FTIR microspectroscopy for high-resolution chemical mapping of single cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2019

DOI: 10.1039/C8AN01543K

Abstract: Coupling synchrotron IR beam to an ATR element enhances spatial resolution suited for high-resolution single cell analysis in biology, medicine and environmental science.

Focal plane array IR imaging at the Australian Synchrotron

Publisher: Elsevier BV

Date: 11-2018

DOI: 10.1016/J.INFRARED.2018.06.022

Fourier Transform Infrared spectroscopy as a novel tool to investigate changes in intracellular macromolecular pools in the marine microalga Chaetoceros muellerii (Bacillariophyceae)

Publisher: Wiley

Date: 18-04-2001

DOI: 10.1046/J.1529-8817.2001.037002271.X

Supramolecular Interactions Playing an Integral Role in the Near-Infrared Raman Excitonic Enhancement Observed in beta-Hematin (Malaria Pigment) and Other Related Heme Derivatives

Publisher: American Chemical Society (ACS)

Date: 30-08-2010

DOI: 10.1021/JP102307S

ATR-FTIR spectroscopy as a quality control system for monitoring the storage of blood products

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1AY01242H

Abstract: ATR-FTIR spectroscopy can be applied to assess storage of blood products.

Synchrotron Infrared Spectroscopy of Cells and Tissue

Publisher: CSIRO Publishing

Date: 2012

DOI: 10.1071/CH11365

Abstract: This paper reviews work carried out in the Centre for Biospectroscopy, Monash University, at the Infrared Microspectroscopy Beamline on the Australian Synchrotron since the first synchrotron light. It discusses the attributes and advantages of the beamline for chemical spectroscopy and imaging of cellular and tissue s les and briefly summarizes new techniques that will come online in the near future.

Vibrational Spectroscopy in Protein Research

Publisher: Elsevier

Date: 2020

DOI: 10.1016/C2018-0-02644-4

Enseñanza del machine learning y la quimiometría en química analítica mediante propuestas prácticas e interactivas

Publisher: Editorial Universitat Politècnica de València

Date: 13-07-2023

DOI: 10.4995/INRED2023.2023.16679

Resonance Raman microscopy in combination with partial dark-field microscopy lights up a new path in malaria diagnostics

Publisher: Royal Society of Chemistry (RSC)

Date: 2009

DOI: 10.1039/B822603B

Abstract: Our goal is to produce a rapid and accurate diagnostic tool for malaria using resonance Raman spectroscopy to detect small inclusions of haemozoin in Plasmodium falciparum infected red blood cells. In pursuit of this aim we serendipitously discovered a partial dark-field effect generated by our experimental setup, which helps identify in thick blood films potential parasites that are normally difficult to see with conventional bright-field microscopy. The haemozoin deposits 'light up' and these can be selectively targeted with the Raman microscope to confirm the presence or absence of haemozoin by the strong 1569 cm(-1) band, which is a marker for haemozoin. With newly developed imaging Raman microscopes incorporating ultra-sensitive rapid readout CCDs it is possible to obtain spectra with a good signal-to-noise ratio in 1 second. Moreover, images from a smear of potentially infected cells can be recorded and analysed with multivariate methods. The reconstructed images show what appear to be sub-micron-inclusions of haemozoin in some cells indicating that the technique has potential to identify low pigmented forms of the parasite including early trophozoite-stage infected cells. Further work is required to unambiguously confirm the presence of such forms through systematic staining but the results are indeed promising and may lead to the development of a new Raman-based malaria diagnostic.

Near‐Infrared Spectroscopic Characterization of Cardiac and Renal Fibrosis in Fixed and Fresh Rat Tissue

Publisher: Wiley

Date: 11-08-2023

DOI: 10.1002/ANSE.202200030

Abstract: Clinical diagnosis of fibrosis is currently reliant on conventional methods. The current “gold standard” for fibrosis diagnosis is histological examination of a biopsy, which is labour intensive and requires extensive s le preparation. Here we show that a portable handheld near‐infrared spectrometer coupled with machine learning algorithms can discriminate between kidney and cardiac fibrosis in a rat model of kidney failure compared to healthy rats without kidney failure. The most significant changes in the spectra of fibrotic tissue included shifts in absorption bands at 1509, 1581, 1689 and 1725 nm attributed to collagen components. The best discrimination of fibrosis was achieved in kidney tissue (AUC=0.962), which showed a higher level of fibrosis compared to cardiac tissue (AUC=0.882). The results show the potential of the NIR spectroscopy to detect and to quantify fibrosis in the heart and kidney that in the future could be applied as an intraoperative surgical tool to guide surgical procedures.

Fourier-transform infrared spectroscopy as a tool for detecting early lymphocyte activation: a new approach to histocompatibility matching

Publisher: Elsevier BV

Date: 12-2000

DOI: 10.1016/S0198-8859(00)00164-6

Abstract: Fourier transform infrared (FT-IR) spectroscopy due to its speed and sensitivity is becoming an increasingly powerful tool in the study of cell composition. We outline the potential of FT-IR microspectroscopy in monitoring mitogenic and cell mediated lymphocyte activation. We demonstrate the potential of FT-IR spectroscopy in histocompatibility testing by showing that significant spectral differences (p < 0.001, for the mean integrated intensity of phosphodiester band located in the 1142-996 cm(-1) region) exist between lymphocyte cocultures from pairs of HLA matched and mismatched volunteers after only 90 min of incubation. The preliminary results indicate that early spectral changes measured are due to HLA differences between in iduals, although the relative contribution of class I and class II differences has yet to be determined. FT-IR spectroscopy represents a novel approach to histocompatibility matching and the rapidity and sensitivity of the technique indicates a potential role in matching protocols for clinical use, particularly in allogeneic bone marrow transplantation.

Ultraviolet/Visible and Near-Infrared Dual Spectroscopic Method for Detection and Quantification of Low-Level Malaria Parasitemia in Whole Blood

Publisher: American Chemical Society (ACS)

Date: 24-09-2021

DOI: 10.1021/ACS.ANALCHEM.1C02948

FTIR spectroscopy of single live cells in aqueous media by synchrotron IR microscopy using microfabricated sample holders

Publisher: Elsevier BV

Date: 05-2010

DOI: 10.1016/J.VIBSPEC.2010.02.005

Resonance Raman Spectroscopy Reveals New Insight into the Electronic Structure of β-Hematin and Malaria Pigment

Publisher: American Chemical Society (ACS)

Date: 09-07-2004

DOI: 10.1021/JA038691X

Abstract: Resonance Raman spectra of beta-hematin and hemin are reported for a range of excitation wavelengths including 406, 488, 514, 568, 633, 780, 830, and 1064 nm. Dramatic enhancement of A(1g) modes (1570, 1371, 795, 677, and 344 cm(-1)), ring breathing modes (850-650 cm(-1)), and out-of-plane modes including iron-ligand modes (400-200 cm(-1)) were observed when irradiating with 780- and 830-nm laser excitation wavelengths for beta-hematin and to a lesser extent hemin. Absorbance spectra recorded during the transformation of hemin to beta-hematin showed a red-shift of the Soret and Q (0-1) bands, which has been interpreted as excitonic coupling resulting from porphyrin aggregation. A small broad electronic transition observed at 867 nm was assigned to a z-polarized charge-transfer transition d(xy) --> e(g)(pi). The extraordinary band enhancement observed when exciting with near-infrared excitation wavelengths in beta-hematin when compared to hemin is explained in terms of an aggregated enhanced Raman scattering hypothesis based on the intermolecular excitonic interactions between porphyrinic units. This study provides new insight into the electronic structure of beta-hematin and therefore hemozoin (malaria pigment). The results have important implications in the design and testing of new anti-malaria drugs that specifically interfere with hemozoin formation.

From bench to worktop: Rapid evaluation of nutritional parameters in liquid foodstuffs by IR spectroscopy

Publisher: Elsevier BV

Date: 12-2021

DOI: 10.1016/J.FOODCHEM.2021.130442

Synchrotron radiation infrared microspectroscopy of arsenic-induced changes to intracellular biomolecules in live leukemia cells

Publisher: Elsevier BV

Date: 05-2010

DOI: 10.1016/J.VIBSPEC.2010.02.004

Progress in Fourier Transform Infrared Spectroscopic Imaging Applied to Venereal Cancer Diagnosis

Publisher: SAGE Publications

Date: 05-09-2013

DOI: 10.1177/0300985813501340

Abstract: Fourier transform infrared imaging spectroscopy is a powerful technique that provides molecular and spatial information at the single-cell level. We report on the progress of this technology in the field of cancer research, focusing on human cervical cancer because of the inherent difficulty in grading this type of cancer and as a model for venereal cancers in dogs. Using a suite of multivariate imaging processing techniques, we demonstrate the potential of this technique to identify histologic features in the normal epithelium and cervical intraepithelial neoplasia stages I and III. We highlight the advantages and detail the barriers that need to be overcome before implementation of this technology in the clinical environment.

FTIR spectral signature of anticancer drugs. Can drug mode of action be identified?

Publisher: Elsevier BV

Date: 2016

DOI: 10.1016/J.BBAPAP.2015.08.010

Abstract: Infrared spectroscopy has brought invaluable information about proteins and about the mechanism of action of enzymes. These achievements are difficult to transpose to living organisms as all biological molecules absorb in the mid infrared, with usually a high degree of overlap. Deciphering the contribution of each enzyme is therefore almost impossible. On the other hand, small changes in the infrared spectra of cells induced by environmental conditions or drugs may provide an accurate signature of the metabolic shift experienced by the cell as a response to a change in the growth medium. The present paper aims at reviewing the contribution of infrared spectroscopy to the description of small chemical changes that occur in cells when they are exposed to a drug. In particular, this review will focus on cancer cells and anti-cancer drugs. Results accumulated so far tend to demonstrate that infrared spectroscopy could be a very accurate descriptor of the mode of action of anticancer drugs. If confirmed, such a segmentation of potential drugs according to their "mode of action" will be invaluable for the discovery of new therapeutic molecules. This article is part of a Special Issue entitled: Physiological Enzymology and Protein Functions.

Trends in biomedical analysis of red blood cells – Raman spectroscopy against other spectroscopic, microscopic and classical techniques

Publisher: Elsevier BV

Date: 2022

DOI: 10.1016/J.TRAC.2021.116481

Haemoprocessor: A Portable Platform Using Rapid Acoustically Driven Plasma Separation Validated by Infrared Spectroscopy for Point-of-Care Diagnostics

Publisher: MDPI AG

Date: 14-02-2022

DOI: 10.3390/BIOS12020119

Abstract: The identification of biomarkers from blood plasma is at the heart of many diagnostic tests. These tests often need to be conducted frequently and quickly, but the logistics of s le collection and processing not only delays the test result, but also puts a strain on the healthcare system due to the sheer volume of tests that need to be performed. The advent of microfluidics has made the processing of s les quick and reliable, with little or no skill required on the user’s part. However, while several microfluidic devices have been demonstrated for plasma separation, none of them have validated the chemical integrity of the s le post-process. Here, we present Haemoprocessor: a portable, robust, open-fluidic system that utilizes Travelling Surface Acoustic Waves (TSAW) with the expression of overtones to separate plasma from 20× diluted human blood within a span of 2 min to achieve 98% RBC removal. The plasma and red blood cell separation quality/integrity was validated through Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy and multivariate analyses to ascertain device performance and reproducibility when compared to centrifugation (the prevailing gold-standard for plasma separation). Principal Component Analysis (PCA) showed a remarkable separation of 92.21% between RBCs and plasma components obtained through both centrifugation and Haemoprocessor methods. Moreover, a close association between plasma isolates acquired by both approaches in PCA validated the potential of the proposed system as an eminent cell enrichment and plasma separation platform. Thus, compared to contemporary acoustic devices, this system combines the ease of operation, low s le requirement of an open system, the versatility of a SAW device using harmonics, and portability.

In vivo prediction of the nutrient status of individual microalgal cells using Raman microspectroscopy

Publisher: Oxford University Press (OUP)

Date: 10-2007

DOI: 10.1111/J.1574-6968.2007.00861.X

Abstract: An in vivo method for predicting the nutrient status of in idual algal cells using Raman microspectroscopy is described. Raman spectra of cells using 780 nm laser excitation show enhanced bands mainly attributable to chlorophyll a and beta-carotene. The relative intensities of chlorophyll a and beta-carotene bands changed under nitrogen limitation, with chlorophyll a bands becoming less intense and beta-carotene bands more prominent. Although spectra from N-replete and N-starved cell populations varied, each distribution was distinct enough such that multivariate classification methods, such as partial least squares discriminant analysis, could accurately predict the nutrient status of the cells from the Raman spectral data.

Whole-Organism Analysis by Vibrational Spectroscopy

Publisher: Annual Reviews

Date: 12-06-2019

DOI: 10.1146/ANNUREV-ANCHEM-061318-115117

Abstract: Vibrational spectroscopy has contributed to the understanding of biological materials for many years. As the technology has advanced, the technique has been brought to bear on the analysis of whole organisms. Here, we discuss advanced and recently developed infrared and Raman spectroscopic instrumentation to whole-organism analysis. We highlight many of the recent contributions made in this relatively new area of spectroscopy, particularly addressing organisms associated with disease with emphasis on diagnosis and treatment. The application of vibrational spectroscopic techniques to entire organisms is still in its infancy, but new developments in imaging and chemometric processing will likely expand in the field in the near future.

Raman spectroscopy and imaging of whole functional cells

Publisher: SPIE

Date: 16-02-2005

DOI: 10.1117/12.582289

Aggregated Enhanced Raman Scattering in Fe(III)PPIX Solutions: The Effects of Concentration and Chloroquine on Excitonic Interactions

Publisher: American Chemical Society (ACS)

Date: 16-04-2009

DOI: 10.1021/JP811028A

Abstract: Resonance Raman spectra of hematin and hemin solutions are reported for 413 and 514 nm excitation wavelengths. Enhancement of A1g modes (1569 and 1370 cm(-1)) and B1g modes (1124 and 755 cm(-1)) as a function of increased concentration are observed when irradiating with 514 nm laser excitation but not 413 nm. This can be rationalized by considering an excitonic coupling mechanism. As the concentration of hematin increases there is an increased probability of supramolecular interactions between iron(III) protoporphyrin IX (Fe(III)PPIX) units occurring. The Fe(III)PPIX concentration reaches a saturation point in solution and excitonic coupling reaches a maximum causing the enhancement profile to plateau when applying 514 nm excitation. In contrast, when using 413 nm excitation there were no changes in band intensity with increased concentration showing that excitonic coupling through supramolecular interactions for aggregated solutions is wavelength dependent. Electronic absorption spectra show that as the concentration of Fe(III)PPIX increases in solution the Soret band is slightly blue shifted and the Q-band significantly broadens supporting the excitonic hypothesis. Understanding the mechanism that accounts for the Raman photophysical behavior of hemes at high concentrations provided an indirect method to monitor antimalarial drug interactions. A second aim was to investigate chloroquine binding to Fe(III)PPIX-OH/H2O monomers, pi-pi dimers and micro-oxo dimers formed in highly concentrated solutions approaching those of the digestive vacuole of the P. falciparum malaria parasite using excitonic Raman enhancement. It was hypothesized that the Raman excitonic enhancement mechanism could be impeded in heme aggregated solutions by the addition of chloroquine. This would result in a reduction in heme bands associated with the A1g modes including nu4. Resonance Raman spectra recorded using 514 nm excitation show that chloroquine (CQ) acts as a molecular spacer and binds noncovalently through dispersion interactions giving rise to pi-pi interactions, between micro-oxo dimer units of Fe(III)PPIX as evinced by the decrease in intensity of nu4 in the Raman spectrum as a function of increasing CQ mole ratio. In comparison, electronic spectra show that CQ can bind to the unligated face of Fe(III)PPIX-OH/H2O monomers, potentially reducing the formation of pi-pi dimers. This study has important implications in determining the effectiveness of potential antimalarial compounds that are thought to exert their effectiveness by binding through supramolecular interactions to the unligated faces of Fe(III)PPIX-OH/H2O monomers and micro-oxo dimers.

Transflection infrared spectroscopy as a rapid screening tool for urinary 8-isoprostane

Publisher: Elsevier BV

Date: 10-2022

DOI: 10.1016/J.MICROC.2022.107641

FTIR Imaging of Tissues: Techniques and Methods of Analysis

Publisher: Springer Netherlands

Date: 06-12-2013

DOI: 10.1007/978-94-007-7832-0_15

How kanamycin A interacts with bacterial and mammalian mimetic membranes

Publisher: Elsevier BV

Date: 11-2017

DOI: 10.1016/J.BBAMEM.2017.08.016

Abstract: Biological membranes are natural barriers to the transport of molecules and drugs within human bodies. Many antibacterial agents need to cross these membranes to reach their target and elicit specific effects. Kanamycin A belongs to the family of aminoglycoside antibiotics that target cellular RNA to inhibit bacterial and viral replication. Previous studies have shown that aminoglycosides bind to mammalian but disrupt bacterial membranes. In this study, molecular dynamics (MD) simulations and infrared (IR) spectroscopy were applied to investigate the initial, first key interactions of kanamycin A, as a representative aminoglycoside, with both bacterial and mammalian lipid bilayers at the molecular level. Computational studies revealed strong hydrogen bonding interactions between the hydroxyl and amino groups of the aminoglycoside with the ester carbonyl and phosphate groups of the lipids. IR spectroscopy provided experimental verification of the important role of the lipid's ester carbonyl, phosphate and hydroxyl groups for aminoglycoside binding. The bacterial membrane became disordered upon aminoglycoside addition, whereas the mammalian membrane became stiffer and more ordered. This indicates the bacterial membrane disruption observed by previous studies.

Clinical Spectroscopy: general discussion

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6FD90013E

The effect of common anticoagulants in detection and quantification of malaria parasitemia in human red blood cells by ATR-FTIR spectroscopy.

Publisher: Royal Society of Chemistry (RSC)

Date: 2017

DOI: 10.1039/C6AN02075E

Abstract: Total Reflectance Infrared Spectroscopy (ATR-FTIR) has the potential to become a new diagnostic tool for malaria and other diseases.

Attenuated Total Reflection Fourier Transform Infrared Spectroscopy combined with chemometric modelling for the classification of clinically relevant Enterococci

Publisher: Oxford University Press (OUP)

Date: 28-08-2020

DOI: 10.1111/JAM.14820

A Fourier transform infrared microspectroscopic imaging investigation into an animal model exhibiting glioblastoma multiforme

Publisher: Elsevier BV

Date: 07-2006

DOI: 10.1016/J.BBAMEM.2006.05.004

Abstract: Glioblastoma multiforme (GBM) is a highly malignant human brain tumour for which no cure is available at present. Numerous clinical studies as well as animal experiments are under way with the goal being to understand tumour biology and develop potential therapeutic approaches. C6 cell glioma in the adult rat is a frequently used and well accepted animal model for the malignant human glial tumour. By combining standard analytical methods such as histology and immunohistochemistry with Fourier Transform Infrared (FTIR) microspectroscopic imaging and multivariate statistical approaches, we are developing a novel approach to tumour diagnosis which allows us to obtain information about the structure and composition of tumour tissues that could not be obtained easily with either method alone. We have used a "Stingray" FTIR imaging spectrometer to analyse and compare the compositions of coronal brain tissue sections of a tumour-bearing animal and those from a healthy animal. We have found that the tumour tissue has a characteristic chemical signature, which distinguishes it from tumour-free brain tissue. The physical-chemical differences, determined by image and spectral comparison are consistent with changes in total protein absorbance, phosphodiester absorbance and physical dispersive artefacts. The results indicate that FTIR imaging analysis could become a valuable analytic method in brain tumour research and possibly in the diagnosis of human brain tumours.

Relationships in Gas Chromatography—Fourier Transform Infrared Spectroscopy—Comprehensive and Multilinear Analysis

Publisher: MDPI AG

Date: 13-05-2020

DOI: 10.3390/SEPARATIONS7020027

Abstract: Molecular spectroscopic detection techniques, such as Fourier transform infrared spectroscopy (FTIR), provides additional specificity for isomers where often mass spectrometry (MS) fails, due to similar fragmentation patterns. A hyphenated system of gas chromatography (GC) with FTIR via a light-pipe interface is reported in this study to explore a number of GC–FTIR analytical capabilities. Various compound classes were analyzed—aromatics, essential oils and oximes. Variation in chromatographic peak parameters due to the light-pipe was observed via sequentially-located flame ionization detection data. Unique FTIR spectra were observed for separated mixtures of essential oil isomers having similar mass spectra. Presentation of GC×FTIR allows a ‘comprehensive’-style experiment to be developed. This was used to obtain spectroscopic/separation profiles for interconverting oxime species with their in idual spectra in the overlap region being displayed on a color contour plot. Partial least square regression provides multivariate quantitative analysis of co-eluting cresol isomers derived from GC–FTIR data. The model resulted in an R2 of 0.99. Prediction was obtained with R2 prediction value of 0.88 and RMSEP of 0.57, confirming the method’s suitability. This study explores the potential of GC–FTIR hyphenation and re-iterates its value to derive unambiguous and detailed molecular information which is complementary to MS.

Label-free in vivo Raman microspectroscopic imaging of the macromolecular architecture of oocytes

Publisher: Springer Science and Business Media LLC

Date: 21-08-2017

DOI: 10.1038/S41598-017-08973-0

Abstract: Confocal Raman spectroscopy (CRS) can provide information about oocyte competency through measurement of changes in the macromolecular architecture during oocyte development and maturation. Hitherto most spectroscopic studies have been limited to fixed oocytes due to the inherent difficulties working with live cells. Here we report the first three-dimensional images of living murine oocytes using CRS. We show that fixation induces significant changes in the macromolecular chemistry compared to living oocytes. A band at 1602 cm −1 , assigned to a marker for mitochondria function was found in living oocytes but absent from fixed oocytes providing an in vivo marker. Fixation resulted in significant changes in protein and nucleic acid bands and the spatial distribution of organelles. Raman imaging of Metaphase I and II (MI, MII) and germinal vesicle stage oocytes showed changes in nuclear organisation and cytoplasm macromolecular architecture during these development and maturation stages related to changes in chromosome condensation, mitochondria aggregation and lipid droplet numbers.

Exploring the origin of tip-enhanced Raman scattering; Preparation of efficient TERS probes with high yield

Publisher: Wiley

Date: 02-08-2012

DOI: 10.1002/JRS.3021

Resonance Raman Enhancement of the ν₄ Band in Fe (TMPP)Cl at NIR Laser Excitation Attributed to Supramolecular Interaction

Publisher: Trans Tech Publications, Ltd.

Date: 04-2012

DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.506.222

Abstract: The strong enhancement when applying near-infrared excitation wavelengths, of totally symmetric modes of heme derivatives including β -hematin (malaria pigment), was hypothesized to be due to supramolecular interaction. Specifically, the intensity of the electron density or oxidation state marker band, ν 4 , is in part strongly affected by CH(((X hydrogen bonding interactions when X is an electron-donating entity. Chlorotetra ( p -methoxyphenyl) porphyrinatoiron (III), Fe (TMPP)Cl, is a model compound that supports this hypothesis. The single crystal X-ray structure of Fe (TMPP)Cl, recrystallized by vapor diffusion of diethyl ether into dichloromethane solution, was determined. There are π por ···π por interactions and numerous additional supramolecular interactions in the form of CH···Cl and CH···O, and CH···π hydrogen bond interactions. The corresponding resonance Raman intensity of Fe (TMPP)Cl exhibited great enhancement of the ν 4 band when using 780 and 830 nm laser sources supporting the correlation of the strong CH(((X hydrogen bonding interaction and the strong resonance Raman enhancement of totally symmetric modes, especially ν 4 , observed in malaria pigment supramolecular arrays when applying near-infrared wavelengths.

An investigation into FTIR spectroscopy as a biodiagnostic tool for cervical cancer

Publisher: Wiley

Date: 07-12-1996

DOI: 10.1002/(SICI)1520-6343(1996)2:3<143::AID-BSPY1>3.0.CO;2-9

3‐D Imaging of Biomedical Samples

Publisher: Wiley

Date: 15-04-2009

DOI: 10.1002/9783527628230.CH6

Raman microspectroscopy and imaging provides insights into heme aggregation and denaturation within human erythrocytes

Publisher: SPIE-Intl Soc Optical Eng

Date: 2005

DOI: 10.1117/1.1854678

Abstract: The oxygenation process of a human erythrocyte is monitored using a Raman microimaging technique. Raman images of the 1638 cm(-1) band are recorded in the oxygenated and deoxygenated state using only 120 s of laser exposure and approximately 1 mW of defocused laser power. The images show hemoglobin oxygenating and deoxygenating within the cell. Prolonged laser imaging exposure (<180 s) at low temperatures results in photoinduced and/or thermal degradation. The effect of thermal degradation is investigated by recording spectra of erythrocytes as a function of temperature between 4 and 52 degrees C. Five bands at 1396, 1365, 1248, 972, and 662 cm(-1) are identified as markers for heme aggregation. Raman images recorded of cells after prolonged laser exposure appear to show heme aggregation commencing in the middle and moving toward the periphery of the cell. UV-visible spectra of erythrocytes show the Soret band to be broader and red shifted (approximately 3 nm) at temperatures between 45 and 55 degrees indicative of excitonic interactions. It is postulated that the enhancement of the aggregation marker bands observed at 632.8-nm excitation results primarily from excitonic interactions between the aggregated hemes in response to protein denaturation. The results have important medical implications in detecting and monitoring heme aggregation associated with hemopathies such as sickle cell disease.

Comment on Ultrarapid On-Site Detection of SARS-CoV-2 Infection Using Simple ATR-FTIR Spectroscopy and an Analysis Algorithm: High Sensitivity and Specificity

Publisher: American Chemical Society (ACS)

Date: 08-12-2021

DOI: 10.1021/ACS.ANALCHEM.1C03099

Discriminating the Intraerythrocytic Lifecycle Stages of the Malaria Parasite Using Synchrotron FT-IR Microspectroscopy and an Artificial Neural Network

Publisher: American Chemical Society (ACS)

Date: 11-03-2009

DOI: 10.1021/AC802291A

Abstract: Synchrotron Fourier transform infrared (FT-IR) spectra of fixed single erythrocytes infected with Plasmodium falciparum at different stages of the intraerythrocytic cycle are presented for the first time. Bands assigned to the hemozoin moiety at 1712, 1664, and 1209 cm(-1) are observed in FT-IR difference spectra between uninfected erythrocytes and infected trophozoites. These bands are also found to be important contributors in separating the trophozoite spectra from the uninfected cell spectra in principal components analysis. All stages of the intraerythrocytic lifecycle of the malarial parasite, including the ring and schizont stage, can be differentiated by visual inspection of the C-H stretching region (3100-2800 cm(-1)) and by using principal components analysis. Bands at 2922, 2852, and 1738 cm(-1) assigned to the nu(asym)(CH(2) acyl chain lipids), nu(sym)(CH(2) acyl chain lipids), and the ester carbonyl band, respectively, increase as the parasite matures from its early ring stage to the trophozoite and finally to the schizont stage. Training of an artificial neural network showed that excellent automated spectroscopic discrimination between P. falciparum-infected cells and the control cells is possible. FT-IR difference spectra indicate a change in the production of unsaturated fatty acids as the parasite matures. The ring stage spectrum shows bands associated with cis unsaturated fatty acids. The schizont stage spectrum displays no evidence of cis bands and suggests an increase in saturated fatty acids. These results demonstrate that different phases of the P. falciparum intraerthyrocytic life cycle are characterized by different lipid compositions giving rise to distinct spectral profiles in the C-H stretching region. This insight paves the way for an automated infrared-based technology capable of diagnosing malaria at all intraerythrocytic stages of the parasite's life cycle.

Biofluids and other techniques: general discussion

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6FD90014C

Molecular Characterization of DNA Double Strand Breaks with Tip‐Enhanced Raman Scattering

Publisher: Wiley

Date: 15-11-2013

DOI: 10.1002/ANIE.201307271

Abstract: DNA double strand breaks (DSBs) are deadly lesions that can lead to genetic defects and cell apoptosis. Techniques that directly detect DNA DSBs include scanning electron microscopy, atomic force microscopy (AFM), and fluorescence based approaches. While these techniques can be used to identify DSBs they provide no information on the molecular events occurring at the break. Tip-enhanced Raman scattering (TERS) can provide molecular information from DNA at the nanoscale and in combination with AFM provides a new way to visualize and characterize the molecular structure of DSBs. DSBs result from cleavage at the 3'- and 5'-bonds of deoxyribose upon exposure to UVC radiation based on the observation of POH and methyl/methylene deformation modes enhanced in the TERS spectra. It is hypothesized that strand fragments are hydrogen-terminated at the lesion, indicating the action of free radicals during photon exposure.

Probing the Influence of the Environment on Microalgae Using Infrared and Raman Spectroscopy

Publisher: American Chemical Society

Date: 02-08-2007

DOI: 10.1021/BK-2007-0963.CH007

Monitoring the biochemical alterations in hypertension affected salivary gland tissues using Fourier transform infrared hyperspectral imaging

Publisher: Royal Society of Chemistry (RSC)

Date: 2017

DOI: 10.1039/C6AN02074G

Abstract: FTIR imaging shows biochemical differences between salivary glands from control and hypertensive rats.

Effect of Drying Methods on Protein and DNA Conformation Changes in Lactobacillus rhamnosus GG Cells by Fourier Transform Infrared Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 20-02-2017

DOI: 10.1021/ACS.JAFC.6B05508

Abstract: Microencapsulation protects cells against environmental stress encountered during the production of probiotics, which are used as live microbial food ingredients. Freeze-drying and spray-drying are used in the preparation of powdered microencapsulated probiotics. This study examines the ability of Fourier transform infrared (FTIR) spectroscopy to detect differences in cells exposed to freeze-drying and spray-drying of encapsulated Lactobacillus rhamnosus GG cells. The FTIR analysis clearly demonstrated there were more significant molecular changes in lipid, fatty acid content, protein, and DNA conformation of nonencapsulated compared to encapsulated bacterial cells. The technique was also able to differentiate between spray-dried and freeze-dried cells. The results also revealed the extent of protection from a protein-carbohydrate-based encapsulant matrix on the cells depending on the type drying process. The extent of this protection to the dehydration stress was shown to be less in spray-dried cells than in freeze-dried cells. This suggests that FTIR could be used as a rapid, noninvasive, and real-time measurement technique to detect detrimental drying effects on cells.

Molecular imaging of red blood cells by Raman spectroscopy

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/CH11136

Abstract: Raman spectroscopy allows visualization of 2D and 3D chemical distributions at high spatial resolution in a wide range of s les. It is insensitive to water, which makes it particularly attractive for applications in the biological sciences. At the same time, technical advances have allowed the laser excitation power to be reduced on thermally sensitive s les, without sacrificing acquisition times. This review highlights the analytical and diagnostic potential of Raman imaging techniques by reference to recent studies of red blood cells. In the case of red blood cells infected with low-pigmented forms of the malaria parasite, molecular images reveal sub-micron-inclusions of haemozoin, which suggests that the technique has potential for early-stage diagnosis of the disease.

Parasites under the Spotlight: Applications of Vibrational Spectroscopy to Malaria Research.

Publisher: American Chemical Society (ACS)

Date: 20-04-2018

DOI: 10.1021/ACS.CHEMREV.7B00661

Abstract: New technologies to diagnose malaria at high sensitivity and specificity are urgently needed in the developing world where the disease continues to pose a huge burden on society. Infrared and Raman spectroscopy-based diagnostic methods have a number of advantages compared with other diagnostic tests currently on the market. These include high sensitivity and specificity for detecting low levels of parasitemia along with ease of use and portability. Here, we review the application of vibrational spectroscopic techniques for monitoring and detecting malaria infection. We discuss the role of vibrational (infrared and Raman) spectroscopy in understanding the processes of parasite biology and its application to the study of interactions with antimalarial drugs. The distinct molecular phenotype that characterizes malaria infection and the high sensitivity enabling detection of low parasite densities provides a genuine opportunity for vibrational spectroscopy to become a front-line tool in the elimination of this deadly disease and provide molecular insights into the chemistry of this unique organism.

Removal of blood components from cervical smears: Implications for cancer diagnosis using FTIR spectroscopy

Publisher: Wiley

Date: 23-10-2003

DOI: 10.1002/BIP.10284

Abstract: Red and white cell lysis buffers were investigated to determine their ability to remove blood components from cervical smears prior to IR microspectroscopy. A white cell lysis buffer was effective in increasing the spectral reproducibility and s le homogeneity and in reducing the presence of inflammatory exudate, particularly leukocytes, from cervical smears. The reduction of leukocytes appeared to cause abnormal s les to be grouped with normal s les, resulting in poor discrimination. Despite differences between the cytological and histological diagnoses of cervical abnormalities, the results indicate that the differences seen in the spectra of exfoliated malignant and nonmalignant cervical cells could be due to the presence of inflammation.

Atomic Force Microscopy Combined with Infrared Spectroscopy as a Tool to Probe Single Bacterium Chemistry

Publisher: MyJove Corporation

Date: 15-09-2020

DOI: 10.3791/61728

Crystal Nucleation, Growth, and Morphology of the Synthetic Malaria Pigment β-Hematin and the Effect Thereon by Quinoline Additives:  The Malaria Pigment as a Target of Various Antimalarial Drugs

Publisher: American Chemical Society (ACS)

Date: 10-02-2007

DOI: 10.1021/JA0674183

Abstract: The morphology of micrometer-sized beta-hematin crystals (synthetic malaria pigment) was determined by TEM images and diffraction, and by grazing incidence synchrotron X-ray diffraction at the air-water interface. The needle-like crystals are bounded by sharp {100} and {010} side faces, and capped by {011} and, to a lesser extent, by {001} end faces, in agreement with hemozoin (malaria pigment) crystals. The beta-hematin crystals grown in the presence of 10% chloroquine or quinine took appreciably longer to precipitate and tended to be symmetrically tapered toward both ends of the needle, due to stereoselective additive binding to {001} or {011} ledges. Evidence, but marginal, is presented that additives reduce crystal mosaic domain size along the needle axis, based on X-ray powder diffraction data. Coherent grazing exit X-ray diffraction suggests that the mosaic domains are smaller and less structurally stable than in pure crystals. IR-ATR and Raman spectra indicate molecular based differences due to a modification of surface and bulk propionic acid groups, following additive binding and a molecular rearrangement in the environment of the bulk sites poisoned by occluded quinoline. These results provided incentive to examine computationally whether hemozoin may be a target of antimalarial drugs diethylamino-alkoxyxanthones and artemisinin. A variation in activity of the former as a function of the alkoxy chain length is correlated with computed binding energy to {001} and {011} faces of beta-hematin. A model is proposed for artemisinin activity involving hemozoin nucleation inhibition via artemisinin-beta-hematin adducts bound to the principal crystal faces. Regarding nucleation of hemozoin inside the digestive vacuole of the malaria parasite, nucleation via the vacuole's membranous surface is proposed, based on a reported hemozoin alignment. As a test, a dibehenoyl-phosphatidylcholine monolayer transferred onto OTS-Si wafer nucleated far more beta-hematin crystals, albeit randomly oriented, than a reference OTS-Si.

Crystal Nucleation, Growth, and Morphology of the Synthetic Malaria Pigment β-Hematin and the Effect Thereon by Quinoline Additives:  The Malaria Pig-ment as a Target of Various Antimalarial Drugs  [

Publisher: American Chemical Society (ACS)

Date: 07-04-2007

DOI: 10.1021/JA076888+

Applications of Fourier-Transform Infrared Imaging in Cancer Research

Publisher: American Chemical Society

Date: 02-08-2007

DOI: 10.1021/BK-2007-0963.CH002

Letter to the Editor

Publisher: Elsevier BV

Date: 10-2003

DOI: 10.1016/S0090-8258(03)00358-5

Imaging of Intact Ovine m. semimembranosus by Confocal Raman Microscopy

Publisher: Springer Science and Business Media LLC

Date: 19-08-2015

DOI: 10.1007/S11947-015-1574-0

Influence of the Sample Preparation Method in Discriminating Candida spp. Using ATR-FTIR Spectroscopy

Publisher: MDPI AG

Date: 28-03-2020

DOI: 10.3390/MOLECULES25071551

Abstract: Several studies have investigated the capacity of ATR-FTIR spectroscopy for fungal species discrimination. However, preparation methods vary among studies. This study aims to ascertain the effect of s le preparation on the discriminatory capacity of ATR-FTIR spectroscopy. Candida species were streaked to obtain colonies and spectra were collected from each preparation type, which included: (a) untreated colonies being directly transferred to the ATR crystal, (b) following washing and (c) following 24-h fixation in formalin. Spectra were pre-processed and principal component analysis (PCA) and K-means cluster analysis (KMC) were performed. Results showed that there was a clear discrimination between preparation types. Groups of spectra from untreated and washed isolates clustered separately due to intense protein, DNA and polysaccharide bands, whilst fixed spectra clustered separately due to intense polysaccharide bands. This signified that s le preparation had influenced the chemical composition of s les. Nevertheless, across preparation types, significant species discrimination was observed, and the polysaccharide (1200–900 cm−1) region was a common critical marker for species discrimination. However, different discriminatory marker bands were observed across preparation methods. Thus, s le preparation appears to influence the chemical composition of Candida s les however, does not seem to significantly impact the species discrimination potential for ATR-FTIR spectroscopy.

A spectroscopic investigation into the binding of novel platinum(IV) and platium(II) anticancer drugs with DNA

Publisher: Elsevier BV

Date: 09-2017

DOI: 10.1016/J.VIBSPEC.2017.02.006

Back matter

Publisher: Royal Society of Chemistry (RSC)

Date: 2013

DOI: 10.1039/C3AN90101G

ATR-FTIR spectroscopy shows changes in ovarian cancer cells after incubation with novel organoamidoplatinum(ii) complexes

Publisher: Royal Society of Chemistry (RSC)

Date: 2018

DOI: 10.1039/C8AN01558A

Abstract: ATR-FTIR spectroscopy has been applied to compare the effect of new organoamidoplatinum( ii ) complexes with cisplatin on cells from a cisplatin-sensitive and a cisplatin-resistant ovarian cancer cell line.

Detection of Human Cholangiocarcinoma Markers in Serum Using Infrared Spectroscopy

Publisher: MDPI AG

Date: 12-10-2021

DOI: 10.3390/CANCERS13205109

Abstract: Cholangiocarcinoma (CCA) is a malignancy of the bile duct epithelium. Opisthorchis viverrini infection is a known high-risk factor for CCA and in found, predominantly, in Northeast Thailand. The silent disease development and ineffective diagnosis have led to late-stage detection and reduction in the survival rate. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) is currently being explored as a diagnostic tool in medicine. In this study, we apply ATR-FTIR to discriminate CCA sera from hepatocellular carcinoma (HCC), biliary disease (BD) and healthy donors using a multivariate analysis. Spectral markers differing from healthy ones are observed in the collagen band at 1284, 1339 and 1035 cm−1, the phosphate band (vsPO2−) at 1073 cm−1, the polysaccharides band at 1152 cm−1 and 1747 cm−1 of lipid ester carbonyl. A Principal Component Analysis (PCA) shows discrimination between CCA and healthy sera using the 1400–1000 cm−1 region and the combined 1800—1700 + 1400–1000 cm−1 region. Partial Least Square-Discriminant Analysis (PLS-DA) scores plots in four of five regions investigated, namely, the 1400–1000 cm−1, 1800–1000 cm−1, 3000–2800 + 1800–1000 cm−1 and 1800–1700 + 1400–1000 cm−1 regions, show discrimination between sera from CCA and healthy volunteers. It was not possible to separate CCA from HCC and BD by PCA and PLS-DA. CCA spectral modelling is established using the PLS-DA, Support Vector Machine (SVM), Random Forest (RF) and Neural Network (NN). The best model is the NN, which achieved a sensitivity of 80–100% and a specificity between 83 and 100% for CCA, depending on the spectral window used to model the spectra. This study demonstrates the potential of ATR-FTIR spectroscopy and spectral modelling as an additional tool to discriminate CCA from other conditions.

Foreword

Publisher: Elsevier BV

Date: 05-2010

DOI: 10.1016/J.VIBSPEC.2010.03.004

Transmission infrared spectroscopy of whole blood – complications for quantitative analysis from leucocyte adhesion during continuous monitoring

Publisher: Wiley

Date: 24-09-2014

DOI: 10.1002/JBIO.201000021

Abstract: Infrared spectroscopy has been applied to analyse glucose and cellular components in whole blood with the aim of developing an online clinical diagnostic and monitoring modality. Leucocyte adsorption onto the CaF 2 windows was observed over a period of several hours under continuous blood flow using a transmission cell of 30 μm path length. This build‐up of cellular material on the windows is responsible for diminishing the s le path length under the flow conditions chosen. The adsorption dynamics have been characterised and their impact on glucose monitoring is reported. For short‐term monitoring ( hours) a standard error of prediction of 11 mg/dL with human citrated blood s les from three different subjects was achieved. Furthermore, the leucocyte build‐up was also reported for porcine EDTA blood monitoring. Consequences and testing opportunities with regard to the first stages in the immune cell reaction to the exposure of body‐foreign materials to anticoagulated whole blood are discussed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

FTIR microspectroscopic study of cell types and potential confounding variables in screening for cervical malignancies

Publisher: Wiley

Date: 1998

DOI: 10.1002/(SICI)1520-6343(1998)4:2<75::AID-BSPY1>3.0.CO;2-R

Vibrational spectroscopy study of the interaction of quinoline antimalarials with ferriprotoporphyrin IX

Publisher: AIP

Date: 2010

DOI: 10.1063/1.3482885

Efficient long-range conduction in cable bacteria through nickel protein wires

Publisher: Springer Science and Business Media LLC

Date: 28-06-2021

DOI: 10.1038/S41467-021-24312-4

Abstract: Filamentous cable bacteria display long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on in idual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating protein shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures.

Synthesis, Structural Characterization and Photodecarbonylation Study of a Dicarbonyl Ruthenium(II)‐Bisquinoline Complex

Publisher: Wiley

Date: 05-2019

DOI: 10.1002/OPEN.201900111

Abstract: A photoactivatable ruthenium(II) carbonyl complex mer,cis ‐[Ru(II)Cl(BisQ)(CO) 2 ]PF 6 2 was prepared using a tridentate bisquinoline ligand (BisQ=(2,6‐diquinolin‐2‐yl)pyridin). Compound 2 was thoroughly characterized by standard analytical methods and single crystal X‐ray diffraction. The crystal structure of the complex cation reveals a distorted octahedral geometry. The decarbonylation upon exposure to 350 and 420 nm light was monitored by UV/VIS absorbance and Fourier transform infrared spectroscopies in acetonitrile and 1 % (v/v) DMSO in water, respectively. The kinetic of the photodecarbonylation has been elucidated by multivariate curve resolution alternating least‐squares analysis. The stepwise decarbonylation follows a serial mechanism. The first decarbonylation occurs very quickly whereas the second decarbonylation step proceeds more slowly. Moreover, the second rate constant is lower in 1 % (v/v) DMSO in water than in acetonitrile. In comparison to 350 nm irradiation, exposure to 420 nm light in acetonitrile results in a lower second rate constant.

Comprehensive Vibrational Spectroscopic Investigation of trans,trans,trans-[Pt(N₃)₂(OH)₂(py)₂], a Pt(IV) Diazido Anticancer Prodrug Candidate

Publisher: American Chemical Society (ACS)

Date: 03-06-2016

DOI: 10.1021/ACS.INORGCHEM.6B00476

Quantification of DNA in simple eukaryotic cells using Fourier transform infrared spectroscopy

Publisher: Wiley

Date: 19-09-2013

DOI: 10.1002/JBIO.201200112

Abstract: A technique capable of detecting and monitoring nucleic acid concentration offers potential in diagnosing cancer and further developing an understanding of the biochemistry of disease. The application of Fourier transform infrared (FTIR) spectroscopy has previously been hindered by the supposed non-Beer-Lambert absorption behavior of DNA in intact cells making elucidation of the DNA bands difficult. We use known composition DNA/hemoglobin standards to successfully estimate the DNA content in avian erythrocyte nuclei (44.2%) and intact erythrocytes (12.8%). Furthermore we demonstrate that the absorption of cellular DNA does follow the Beer-Lambert Law and highlights the role of conformation and hydration in FTIR spectroscopy of biological s les.

Interaction between metal-free porphine and surface Ag atoms through temporal fluctuation of surface-enhanced resonance raman scattering and background-light emission

Publisher: Elsevier

Date: 2007

DOI: 10.1016/S1574-0641(07)80015-5

Quantitative determination of polyphosphate in sediments using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and partial least squares regression

Publisher: Royal Society of Chemistry (RSC)

Date: 2012

DOI: 10.1039/C2AN35289C

Abstract: Phosphorus (P) is a major cause of eutrophication and subsequent loss of water quality in freshwater ecosystems. A major part of the flux of P to eutrophic lake sediments is organically bound or of biogenic origin. Despite the broad relevance of polyphosphate (Poly-P) in bioremediation and P release processes in the environment, its quantification is not yet well developed for sediment s les. Current methods possess significant disadvantages because of the difficulties associated with using a single extractant to extract a specific P compound without altering others. A fast and reliable method to estimate the quantitative contribution of microorganisms to sediment P release processes is needed, especially when an excessive P accumulation in the form of polyphosphate (Poly-P) occurs. Development of novel approaches for application of emerging spectroscopic techniques to complex environmental matrices such as sediments significantly contributes to the speciation models of P mobilization, biogeochemical nutrient cycling and development of nutrient models. In this study, for the first time Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy in combination with partial least squares (PLS) was used to quantify Poly-P in sediments. To reduce the high absorption matrix components in sediments such as silica, a physical extraction method was developed to separate sediment biological materials from abiotic particles. The aim was to achieve optimal separation of the biological materials from sediment abiotic particles with minimum chemical change in the s le matrix prior to ATR-FTIR analysis. Using a calibration set of 60 s les for the PLS prediction models in the Poly-P concentration range of 0-1 mg g(-1) d.w. (dry weight of sediment) (R(2) = 0.984 and root mean square error of prediction RMSEP = 0.041 at Factor-1) Poly-P could be detected at less than 50 μg g(-l) d.w. Using this technique, there is no solvent extraction or chemical treatment required, s le preparation is minimal and simple, and the analysis time is greatly reduced. The results from this study demonstrated the potential of ATR FT-IR spectroscopy as an alternative method to study Poly-P in sediments.

Correlation of atomic force microscopy and Raman micro-spectroscopy to study the effects of ex vivo treatment procedures on human red blood cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2010

DOI: 10.1039/B919245J

Abstract: The effects of fixation and dehydration on the distribution of heme-based molecules inside red blood cells and the structural integrity of the cells have been investigated using Raman mapping and AFM topographic imaging. A strong correlation was observed between the thickness of the cells as determined from AFM images and the intensity of the characteristic heme bands in the Raman maps, demonstrating that heme compounds are relatively evenly distributed inside dried and fixed cells in the majority of cases. The exception occurred when cells were dried in phosphate buffered saline, where more hemichrome appears close to the periphery of the cell despite the AFM image showing a plateau like topography. Using neat formaldehyde solution as a fixative is inadequate for a complete structural preservation and results in diffusion of hemoglobin into the surrounding area. However, a mixture of formaldehyde (3%) and glutaraldehyde (0.1%) in buffer was found to be sufficient to retain the structural integrity of cells with minimal autofluorescence. This protocol was also suitable for red blood cells infected with Plasmodium falciparum parasites, and preserved the characteristic knob-like structures on the infected red blood cell surface.

Determination of the secondary structure of proteins in different environments by FTIR‐ATR spectroscopy and PLS regression

Publisher: Wiley

Date: 19-05-2008

DOI: 10.1002/BIP.21022

Abstract: The secondary structures of proteins (alpha-helical, beta-sheet, beta-turn, and random coil) in the solid state and when bound to polymer beads, containing immobilized phenyl and butyl ligands such as those as commonly employed in hydrophobic interaction chromatography, have been investigated using FTIR-ATR spectroscopy and partial least squares (PLS) methods. Proteins with known structural features were used as models, including 12 proteins in the solid state and 7 proteins adsorbed onto the hydrophobic surfaces. A strong PLS correlation was achieved between predictions derived from the experimental data for 4 proteins adsorbed onto the phenyl-modified beads and reference data obtained from the X-ray crystallographic structures with r(2) values of 0.9974, 0.9864, 0.9924, and 0.9743 for alpha-helical, beta-sheet, beta-turn, and random coiled structures, respectively. On the other hand, proteins adsorbed onto the butyl sorbent underwent greater secondary structural changes compared to the phenyl sorbent as evidenced from the poorer PLS r(2) values (r(2) are 0.9658, 0.9106, 0.9571, and 0.9340). The results thus indicate that the secondary structures for these proteins were more affected by the butyl sorbent, whereas the secondary structure remains relatively unchanged for the proteins adsorbed onto the phenyl sorbent. This study has important ramifications for understanding the nature of protein secondary structural changes following adsorption onto hydrophobic sorbent surfaces. This knowledge could also enable the development of useful protocols for enhancing the chromatographic purification of proteins in their native bioactive states.

Resonance Raman and UV‐Visible Microscopy Reveals that Conditioning Red Blood Cells with Repeated Doses of Sodium Dithionite Increases Haemoglobin Oxygen Uptake

Publisher: Wiley

Date: 13-04-2017

DOI: 10.1002/SLCT.201700190

Divalent cations stabilize the aggregation of sulfated glycoproteins in the adhesive nanofibers of the biofouling diatom Toxarium undulatum

Publisher: Royal Society of Chemistry (RSC)

Date: 2008

DOI: 10.1039/B715455K

Characterization of freeze-dried oxidized human red blood cells for pre-transfusion testing by synchrotron FTIR microspectroscopy live-cell analysis

Publisher: Royal Society of Chemistry (RSC)

Date: 2023

DOI: 10.1039/D2AN02001G

Abstract: Oxidative treatment of human red blood cells (RBCs) prior to freeze-drying appears to stabilize the RBCs to withstand dried storage at room temperature.

A star shaped acoustofluidic mixer enhances rapid malaria diagnostics via cell lysis and whole blood homogenisation in 2 seconds

Publisher: Royal Society of Chemistry (RSC)

Date: 2022

DOI: 10.1039/D2LC00195K

Abstract: Shear stresses generated by a silicon resonator embedded inside a microfluidic channel can rapidly and effectively lyse cells and homogenise whole blood. This significantly improves sensitivity of ATR-FTIR spectroscopy based diagnostic tests.

Addressing Delicate and Variable Cancer Morphology in Spectral Histopathology Using Canine Visceral Hemangiosarcoma

Publisher: American Chemical Society (ACS)

Date: 30-08-2021

DOI: 10.1021/ACS.ANALCHEM.0C05190

Raman excitation wavelength investigation of single red blood cells in vivo

Publisher: Wiley

Date: 07-2002

DOI: 10.1002/JRS.870

In vivo atomic force microscopy–infrared spectroscopy of bacteria

Publisher: The Royal Society

Date: 03-2018

DOI: 10.1098/RSIF.2018.0115

Abstract: A new experimental platform for probing nanoscale molecular changes in living bacteria using atomic force microscopy–infrared (AFM–IR) spectroscopy is demonstrated. This near-field technique is eminently suited to the study of single bacterial cells. Here, we report its application to monitor dynamical changes occurring in the cell wall during cell ision in Staphylococcus aureus using AFM to demonstrate the ision of the cell and AFM–IR to record spectra showing the thickening of the septum . This work was followed by an investigation into single cells, with particular emphasis on cell-wall signatures, in several bacterial species. Specifically, mainly cell wall components from S. aureus and Escherichia coli containing complex carbohydrate and phosphodiester groups, including peptidoglycans and teichoic acid, could be identified and mapped at nanometre spatial resolution. Principal component analysis of AFM–IR spectra of six living bacterial species enabled the discrimination of Gram-positive from Gram-negative bacteria based on spectral bands originating mainly from the cell wall components. The ability to monitor in vivo molecular changes during cellular processes in bacteria at the nanoscale opens a new platform to study environmental influences and other factors that affect bacterial chemistry.

Raman spectroscopic analysis of Lactobacillus rhamnosus GG in response to dehydration reveals DNA conformation changes

Publisher: Wiley

Date: 31-05-2016

DOI: 10.1002/JBIO.201600046

Abstract: Dehydration of bacterial cells elicits cellular stress responses in bacteria. Microencapsulation has been used to protect cells against the environmental stress. In this study, Confocal Raman Spectroscopy was used to examine DNA changes in the chemical composition of non-encapsulated and microencapsulated Lactobacillus rhamnosus GG and the reversibility of these changes upon freeze drying and rehydration. The viability of cells upon freeze drying was also enumerated using culture methods and membrane integrity was measured using BacLight Live/Dead staining. Raman analyses show changes in the spectral features associated with various biochemical compounds, which are interpreted as the result of detrimental freeze drying effects on the bacterial cells. Specifically, analyses based on Principal Components Analysis (PCA) of Raman spectra, confirm that microencapsulation protects cells from environmental stress. The results also reveal a B- to A-like DNA conformation change in dormant cells that provided insights into the extent of reversibility of this transition upon rehydration. The extent of this reversibility is less in non-encapsulated than in microencapsulated cells. These findings indicate the potential application of Raman spectroscopy in rapid sensing of microbial dehydration stress responses.

Detection of Antimicrobial Resistance-Related Changes in Biochemical Composition of Staphylococcus aureus by Means of Atomic Force Microscopy-Infrared Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 22-11-2019

DOI: 10.1021/ACS.ANALCHEM.9B01671

Abstract: The development of antimicrobial resistance (AMR) resulting from widespread antibiotic usage is occurring at an alarming pace, much faster than our understanding of the mechanisms behind resistance. Knowledge about resistance-related phenotypic and genotypic changes is critical for the development of new drugs. Here, we identify changes in the chemical composition of

ATR‐FTIR Spectroscopy for Early Detection of Diabetic Kidney Disease

Publisher: Wiley

Date: 16-01-2023

DOI: 10.1002/ANSE.202200094

Abstract: Current screening methods for diabetic kidney disease (DKD), characterized by albumin excretion in urine, are expensive or only identify patients in late disease stages. Hence, there is need for a cost‐effective, quick, and portable screening tool which identifies patients at DKD onset. Here we report that ultracentrifugation coupled with infrared spectroscopy and machine learning can identify and quantify low level microalbuminuria in urine s les from a cohort of diabetic patients (n=155) and controls (n=22). Independent testing of the methods indicated that classification analysis discriminated between normo‐ and micro/macroalbuminuric s les with sensitivity of % and specificity of %. Regression methods quantified albumin concentration in the s les with error values of 17 and 44 mg/L for normo‐ and microalbuminuric patients. Using only 700 μL of s le, this approach identifies patients at an earlier stage of disease than a urinary dipstick, whilst also yielding results cheaper and faster than the albumin to creatinine ratio.

Novel in situ methodology to observe the interactions of chemotherapeutical Pt drugs with DNA under physiological conditions

Publisher: Royal Society of Chemistry (RSC)

Date: 2014

DOI: 10.1039/C4DT00861H

Abstract: The binding of the antitumor drug cisplatin with DNA was determined by means of in situ resonant inelastic X-ray scattering (RIXS) spectroscopy.

Correction: The importance of hydration and DNA conformation in interpreting infrared spectra of cells and tissues

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C5CS90121A

Abstract: Correction for ‘The importance of hydration and DNA conformation in interpreting infrared spectra of cells and tissues’ by Bayden R. Wood et al. , Chem. Soc. Rev. , 2015, DOI: 10.1039/c5cs00511f.

Raman imaging of hemozoin within the food vacuole of Plasmodium falciparum trophozoites

Publisher: Wiley

Date: 21-10-2003

DOI: 10.1016/S0014-5793(03)00975-X

Abstract: Micro-Raman spectra of hemozoin encapsulated within the food vacuole of a Plasmodium falciparum-infected erythrocyte are presented. The spectrum of hemozoin is identical to the spectrum of beta-hematin at all applied excitation wavelengths. The unexpected observation of dramatic band enhancement of A(1g) modes including nu(4) (1374 cm(-1)) observed when applying 780 nm excitation enabled Raman imaging of hemozoin in the food vacuole. This unusual enhancement, resulting from excitonic coupling between linked porphyrin moieties in the extended porphyrin array, enables the investigation of hemozoin within its natural environment for the first time.

Resonant Raman Scattering of Heme Molecules in Cells and in the Solid State

Publisher: Wiley

Date: 15-10-2007

DOI: 10.1002/9780470283172.CH8

Studies of Carbon Monoxide Release from Ruthenium(II) Bipyridine Carbonyl Complexes upon UV-Light Exposure

Publisher: American Chemical Society (ACS)

Date: 03-05-2017

DOI: 10.1021/ACS.INORGCHEM.7B00599

Abstract: The UV-light-induced CO release characteristics of a series of ruthenium(II) carbonyl complexes of the form trans-Cl[RuLCl

Shedding new light on the molecular architecture of oocytes using a combination of synchrotron fourier transform-infrared and raman spectroscopic mapping

Publisher: American Chemical Society (ACS)

Date: 05-11-2008

DOI: 10.1021/AC8015483

Fourier transform infrared imaging as a method for detection of HLA class I expression in melanoma without the use of antibody.

Publisher: Wiley

Date: 04-2007

DOI: 10.1111/J.1399-0039.2006.00775.X

Abstract: Human leukocyte antigen (HLA) class I expression in melanoma is usually assessed using immunohistochemical staining. Here we report on the use of Fourier transform infrared (FTIR) hyperspectral imaging, a method widely used in two-dimensional analysis of chemical components, to study HLA class I expression in tissue. Two-dimensional cluster colour images derived from unsupervised hierarchical cluster analysis of FTIR hyperspectral data on melanoma sections were compared with consecutive sections that were immunohistochemically stained for class I expression. HLA-class-I-positive and -negative areas were differentiated by FTIR cluster images in all eight melanoma sections investigated without the need for antibody attachment. FTIR imaging enables the distinction of HLA-class-I-positive from class-I-negative areas in melanoma. This method is accurate, rapid and cost-effective.

Gas chromatography–Fourier transform infrared spectroscopy reveals dynamic molecular interconversion of oximes

Publisher: Royal Society of Chemistry (RSC)

Date: 2019

DOI: 10.1039/C9AN00990F

Abstract: Oxime E / Z isomers interconvert on GC columns they can be in idually monitored using FTIR to provide profiles of each isomer.

High resolution FTIR imaging provides automated discrimination and detection of single malaria parasite infected erythrocytes on glass

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C5FD00181A

Abstract: New highly sensitive tools for malaria diagnostics are urgently needed to enable the detection of infection in asymptomatic carriers and patients with low parasitemia. In pursuit of a highly sensitive diagnostic tool that can identify parasite infections at the single cell level, we have been exploring Fourier transform infrared (FTIR) microscopy using a Focal Plane Array (FPA) imaging detector. Here we report for the first time the application of a new optic configuration developed by Agilent that incorporates 25× condenser and objective Cassegrain optics with a high numerical aperture (NA = 0.81) along with additional high magnification optics within the microscope to provide 0.66 micron pixel resolution (total IR system magnification of 61×) to diagnose malaria parasites at the single cell level on a conventional glass microscope slide. The high quality images clearly resolve the parasite's digestive vacuole demonstrating sub-cellular resolution using this approach. Moreover, we have developed an algorithm that first detects the cells in the infrared image, and secondly extracts the average spectrum. The average spectrum is then run through a model based on Partial Least Squares-Discriminant Analysis (PLS-DA), which diagnoses unequivocally the infected from normal cells. The high quality images, and the fact this measurement can be achieved without a synchrotron source on a conventional glass slide, shows promise as a potential gold standard for malaria detection at the single cell level.

Detection and Identification of Wolbachia pipientis Strains in Mosquito Eggs Using Attenuated Total Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy

Publisher: SAGE Publications

Date: 09-07-2021

DOI: 10.1177/00037028211027140

Abstract: The global fight against mosquito-borne viral diseases has in recent years been bolstered by the introduction of the endosymbiotic bacteria Wolbachia to vector populations, which in host mosquitoes suppresses the transmissibility of several viruses. Researchers engaged on this front of the battle often need to know the Wolbachia infection status of in idual mosquitoes, as the intervention progresses and the mosquitoes become established in the target population. Previously, we successfully applied attenuated total reflection Fourier transform infrared spectroscopy to the detection of Wolbachia in adult Aedes aegypti mosquitoes here we apply the same principles to Aedes eggs, with sensitivity and selectivity 0.95. Further, we successfully distinguish between infections in eggs of the wMel and wMelPop strains of Wolbachia pipientis, with a classification error of 3% . The disruption of host lipid profile by Wolbachia is found to be a key driver in spectral differences between these s le classes.

Plasmonic enhancement enabled by silver nanotriangles in Raman spectra of methylene blue

Publisher: Institute of Advanced Studies, Nanyang Technological University

Date: 12-2020

DOI: 10.32655/ASC_8-10_DEC2020.64

Resonant Mie scattering (RMieS) correction applied to FTIR images of biological tissue samples

Publisher: Royal Society of Chemistry (RSC)

Date: 2012

DOI: 10.1039/C1AN15628D

Abstract: Recently a resonant Mie scattering (RMieS) correction approach has been developed and demonstrated to be effective for removing the baseline distortions that compromise the raw data in in idual spectra. In this paper RMieS correction is extended to FTIR images of a tissue section from biopsy of the human cervical transformation zone and a coronal tissue section of a Wistar rat brain and compared to the uncorrected images. It is shown that applying RMieS correction to FTIR images a) removes baseline distortions from the image spectra and thus reveals previously hidden information on spatial variation of chemical contents within the tissue and b) can lead to improved automatic tissue feature classification through multivariate cluster analysis.

Influence of DFT Functionals and Solvation Models on the Prediction of Far-Infrared Spectra of Pt-Based Anticancer Drugs: Why Do Different Complexes Require Different Levels of Theory?

Publisher: American Chemical Society (ACS)

Date: 13-03-2019

DOI: 10.1021/ACSOMEGA.8B03455

Fourier Transform Infrared microspectroscopy and chemometrics as a tool for the discrimination of cyanobacterial strains

Publisher: Elsevier BV

Date: 10-1999

DOI: 10.1016/S0031-9422(99)00212-5

Fourier transform infrared imaging and small angle x-ray scattering as a combined biomolecular approach to diagnosis of breast cancer

Publisher: Wiley

Date: 29-04-2008

DOI: 10.1118/1.2890391

Abstract: Fourier transform infrared (FTIR) microspectroscopic imaging and small angle x-ray scattering (SAXS) were combined to investigate the supramolecular structure of collagen from 27 tissue sections from patients undergoing mastectomy, excisional biopsy, or mammoplasty. Both techniques were correlated by matching the scattering profile from the SAXS data with the integrated area of the infrared collagen region (1300-1180 cm(-1)). The FTIR spectral profiles and multivariate analysis of various tissue components showed consistent differences between all major tissue components, particularly between cancer and normal tissue cells. Analysis of the SAXS data revealed broad differences between cancer and normal tissue, but were inconclusive due to the small s le size. Parameters were extracted from each technique in relation to their characterization of collagen to reveal a good correlation between the two techniques, which diagnostically parallels with gold-standard Hematoxylin and Eosin (H&E) stained sections. The results show that the integrated area of collagen region in the FTIR spectrum for cancerous s les is greater than that for noncancerous s les indicating collagen disorder. This supports the notion that collagen is structurally disrupted in cancer tissue consistent with the interpretation of the SAXS data. Overall, both these techniques successfully distinguished cancer from normal breast tissue. Integration of these two techniques was able to better segregate cancer as well as provide a more complete understanding of the differences in collagen on all structural levels during breast cancer development.

ATR-Spin: an open-source 3D printed device for direct cytocentrifugation onto attenuated total reflectance crystals

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1LC00813G

Abstract: The 3d printed system presented integrates isolation, preconcentration, and measurement of infrared spectra of cells from biofluids, enabling enhanced specific infrared spectra of cells down to 10 cells μL −1 .

Identification of Glucose-6 Phosphate Dehydrogenase Deficient Patients Using Attenuated Total Reflection Fourier Transform Infrared Spectroscopy Using Partial Least Squares Discriminant Analysis in Aq

Publisher: SAGE Publications

Date: 05-2023

DOI: 10.1177/00037028231170851

Abstract: Glucose-6 phosphate dehydrogenase (G6PD) deficiency is an X-linked blood disease that affects 400 million people globally and is especially prevalent in malaria-endemic regions. A significant portion of carriers are asymptomatic and undiagnosed posing complications in the eradication of malaria as it restricts the types of drugs used for malaria treatment. A simple and accurate diagnosis of the deficiency is vital in the eradication of malaria. In this study, we investigate the potential of attenuated total reflection Fourier transform infrared spectroscopy (ATR FT-IR) as a diagnostic technique for G6PD deficiency. Venous blood s les were collected in lithium heparin anticoagulant tubes from G6PD partial and fully deficient volunteers, n = 17, and normal volunteers, n = 59, in Khon Kaen, Thailand. Spectra of aqueous and dry s les were acquired of whole blood, plasma, and red blood cells, and modeled using partial least squares discriminant analysis (PLS-DA). PLS-DA modeling resulted in a sensitivity of 0.800 and specificity of 0.800 correctly classifying fully deficient participants as well as a majority of partially deficient females who are often misdiagnosed as normal by current screening methods. The viability of utilizing aqueous s les has always been hindered by the variability of hydration in the s le, but by employing multicurve curve resolution-alternating least squares to subtract water from each s le we are able to produce high-quality spectra with minimized water contributions. The approach shows proof of principle that ATR FT-IR combined with multivariate data analysis could become a frontline screening tool for G6PD deficiency by improving tailored drug treatments and ultimately saving lives.

Synchrotron Fourier transform infrared (FTIR) analysis of single living cells progressing through the cell cycle

Publisher: Royal Society of Chemistry (RSC)

Date: 2013

DOI: 10.1039/C3AN00316G

Abstract: The application of FTIR spectroscopy to disease diagnosis requires a thorough knowledge of the spectroscopy associated with the cell cycle to discern disease markers from normal cellular events. We have applied synchrotron FTIR spectroscopy to monitor cells at different phases of the cell cycle namely G1, S and G2 phases. By applying Principal component analysis (PCA) from three independent trials we show clustering on a 2-dimensional scores plots (PC1 versus PC2) from cell spectra only two hours apart within the cell cycle. The corresponding PCA Loadings Plots indicate the clustering is primarily based on changes to the overall concentration of nucleic acids, proteins and lipids. During the first ten hours post mitosis, cells are observed to increase in protein and decrease in both lipid and nucleic acid concentration. During the synthesis phase, (beginning 9-11 hours post-mitosis) the PCA Loadings Plots show the accumulation of lipids within the cell as well the duplication of the genome as evidenced by strong DNA contributions. In the 4-6 hours following the synthesis phase, the cells once again accumulate protein while the relative nucleic acid and lipid concentrations decrease. These results, in comparison to previous studies on dehydrated cells, show previously unresolvable biochemical information as well as highlighting the advantages of FTIR spectroscopy applied to single living cells.

Visible microspectrophotometry coupled with machine learning to discriminate the erythrocytic life cycle stages of P. falciparum malaria parasites in functional single cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2022

DOI: 10.1039/D2AN00274D

Abstract: Visible microspectroscopy combined with machine learning is able to detect and quantify functional malaria infected erythrocytes at different stages of the P. falciparum erythrocytic life cycle.

Preface

Publisher: Elsevier

Date: 2020

DOI: 10.1016/B978-0-12-818610-7.00024-4

Resonance Raman spectroscopy of hemoglobin in red blood cells

Publisher: Elsevier

Date: 2020

DOI: 10.1016/B978-0-12-818610-7.00013-X

Proof of concept study for the detection and quantification of low molecular weight human serum proteomes using a miniature near-infrared spectrometer

Publisher: Institute of Advanced Studies, Nanyang Technological University

Date: 12-2020

DOI: 10.32655/ASC_8-10_DEC2020.52

A three-dimensional multivariate image processing technique for the analysis of FTIR spectroscopic images of multiple tissue sections

Publisher: Springer Science and Business Media LLC

Date: 04-2006

DOI: 10.1186/1471-2342-6-12

NIR “matchbox size” spectrometer can quantify and detect malaria infection in Plasmodium falciparum infected red blood cells

Publisher: Institute of Advanced Studies, Nanyang Technological University

Date: 12-2020

DOI: 10.32655/ASC_8-10_DEC2020.51

Comparison of transflection and transmission FTIR imaging measurements performed on differentially fixed tissue sections

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4AN02034K

Abstract: FTIR microscopy of adjacent sections of tissue measured by transmission and transflection shows comparable images after UHCA.

Detection of Nano-Oxidation Sites on the Surface of Hemoglobin Crystals Using Tip-Enhanced Raman Scattering

Publisher: American Chemical Society (ACS)

Date: 17-02-2012

DOI: 10.1021/NL2044106

Abstract: Hemoglobin nanocrystals were analyzed with tip-enhanced Raman scattering (TERS), surface-enhanced resonance Raman scattering (SERRS) and conventional resonance Raman scattering (RRS) using 532 nm excitation. The extremely high spatial resolution of TERS enables selective enhancement of heme, protein, and amino acid bands from the crystal surface not observed in the SERRS or RRS spectra. Two bands appearing at 1378 and 1355 cm(-1) assigned to the ferric and ferrous oxidation state marker bands, respectively, were observed in both TERS and SERRS spectra but not in the RRS spectrum of the bulk s le. The results indicate that nanoscale oxidation changes are occurring at the hemoglobin crystal surface. These changes could be explained by oxygen exchange at the crystal surface and demonstrate the potential of the TERS technique to obtain structural information not possible with conventional Raman microscopy.

Synchrotron-Based Microspectroscopic Study on the Effects of Heat Treatments on Cotyledon Tissues in Yellow-Type Canola (Brassica) Seeds

Publisher: American Chemical Society (ACS)

Date: 18-07-2013

DOI: 10.1021/JF4012517

Abstract: Synchrotron-based infrared (IR) microspectroscopy is able to reveal structural features of biomaterials within intact tissue at both cellular and molecular levels. Heat-related treatments have been used to improve nutrient availability of canola seeds and meal. However, hitherto, there has been no study on the sensitivity and response of each layer in canola seeds to heat-related treatments. It is not known which layer (epiderm/mucllage, spermoderm, endosperm, or cotyledon) is the most sensitive to heat when heat treatment is applied to the seeds. Traditional wet chemical analysis is unable to answer such questions. The objective of this study is to use synchrotron IR microspectroscopy with multivariate molecular spectral analyses as a research tool to study heat treatment effects in a fast way on the structural changes in cotyledon tissues of yellow-type canola (Brassica) seeds among raw (treatment code "A"), wet heating (autoclaving at 121 °C for 60 min, treatment code "B"), and dry heating (dry roasting at 120 °C for 60 min, treatment code "C"). The hypothesis of this study was that different heat treatments have different heat penetration abilities on cotyledon tissues in yellow-type canola seeds. The multivariate analytical tools principal component analysis (PCA) and agglomerative hierarchal cluster analysis (AHCA) were applied to investigate variance and groupings within the spectral data set [whole spectral range of ca. 4000-650 cm(-1), spectral range of ca. 1300-900 cm(-1) (cellulose or saccarides), spectral range of ca. 1800-1500 cm(-1) (secondary structures of protein) and spectral range of ca. 1500-1300 cm(-1) (bending motion of methylene and methyl group this change is consistent with the change in the range of ca. 3000-2800 cm(-1))]. The results showed that there were no clear cluster and groups formed in the cotyledon tissues among the three treatments (A, B, and C). There were no clear distinguished responses of the cotyledon tissues to different types of heat treatments using multivariate molecular spectral analyses. The results indicate that the cotyledon tissues might not be sufficiently penetrated by both heat treatments (autoclaving and dry roasting) under the specified conditions. A future study is needed to analyze in idual functional group band intensity among the treatments using univariate molecular spectral analysis to confirm multivariate PCA and cluster analyses.

Micro‐Raman characterization of high‐ and low‐spin heme moieties within single living erythrocytes

Publisher: Wiley

Date: 2002

DOI: 10.1002/BIP.10120

Abstract: Raman microspectroscopy was applied to monitor porphyrin perturbation associated with the tense‐relaxed (T → R) state transition of hemoglobin (Hb) within a single red blood cell. The spectra exhibited dramatic changes in the spin state region (1650–1500 cm −1 ) and the methine CH deformation region (1250–1200 cm −1 ) between the 27‐ and 54‐min interval following reoxygenation. Principal components analysis revealed a sigmoidal curve when the PC1 scores versus time were plotted. The inflection point on the curve corresponded to the T → R transition point spectrum, indicating the cell is composed of Hb in a mixture of spin states. The results of this work illustrate the dynamics of porphyrin perturbation during erythrocyte respiration and may have applications in the diagnosis and treatment of red blood cell disorders including thalassemia and sickle cell anemia. © 2002 Wiley Periodicals, Inc. Biopolymers (Biospectroscopy) 67: 259–262, 2002

Mapping of nutrient-induced biochemical changes in living algal cells using synchrotron infrared microspectroscopy

Publisher: Oxford University Press (OUP)

Date: 08-2005

DOI: 10.1016/J.FEMSLE.2005.06.021

Abstract: High quality Fourier transform infrared (FTIR) spectra were acquired from living Micrasterias hardyi cells maintained in an IR transparent flow-through cell using a FTIR microscope coupled to a synchrotron light source. Spectral maps of living, nutrient-replete cells showed band intensities consistent with the known location of the nucleus and the chloroplasts. These were very similar to maps acquired from fixed, air-dried cells. Bands due to lipids were lowest in absorbance in the region of the nucleus and highest in the chloroplast region and this trend was reversed for the absorbance of bands attributed to protein. Spectra acquired in 10 microm steps across living phosphorus-starved (P-starved) cells, repeated approximately every 30 min, were consistent over time, and bands correlated well with the known position of the nucleus and the observed chloroplasts, corroborating the observations with replete cells. Experiments in which missing nutrients were re-supplied to starved cells showed that cells could be maintained in a functional state in the flow-through cell for up to one day. Nitrogen-starved cells re-supplied with N showed an increase in lipid in all positions measured across the cell over a 23 h period of re-supply, with the largest increases occurring in positions where the chloroplasts were observed. Re-supply of phosphorus to P-starved cells produced no changes in bands attributable to lipid or protein. Due to their thin cell body ( approximately 12 microm) and large diameter ( approximately 300 microm) Micrasterias sp. make an ideal spectroscopic model to study nutrient kinetics in algal cells.

Fourier-Transform Infra-Red Microspectroscopy Can Accurately Diagnose Colitis and Assess Severity of Inflammation

Publisher: MDPI AG

Date: 05-03-2022

DOI: 10.3390/IJMS23052849

Abstract: The diagnosis and management of inflammatory bowel disease relies on histological assessment, which is costly, subjective, and lacks utility for point-of-care diagnosis. Fourier-transform infra-red spectroscopy provides rapid, non-destructive, reproducible, and automatable label-free biochemical imaging of tissue for diagnostic purposes. This study characterises colitis using spectroscopy, discriminates colitis from healthy tissue, and classifies inflammation severity. Hyperspectral images were obtained from fixed intestinal sections of a murine colitis model treated with cell therapy to improve inflammation. Multivariate analyses and classification modelling were performed using supervised and unsupervised machine-learning algorithms. Quantitative analysis of severe colitis showed increased protein, collagen, and nucleic acids, but reduced glycogen when compared with normal tissue. A partial least squares discriminant analysis model, including spectra from all intestinal layers, classified normal colon and severe colitis with a sensitivity of 91.4% and a specificity of 93.3%. Colitis severity was classified by a stacked ensemble model yielding an average area under the receiver operating characteristic curve of 0.95, 0.88, 0.79, and 0.85 for controls, mild, moderate, and severe colitis, respectively. Infra-red spectroscopy can detect unique biochemical features of intestinal inflammation and accurately classify normal and inflamed tissue and quantify the severity of inflammation. This is a promising alternative to histological assessment.

Focal plane array infrared imaging: a new way to analyse leaf tissue

Publisher: Wiley

Date: 11-10-2006

DOI: 10.1111/J.1469-8137.2006.01881.X

Abstract: * Here, a new approach to macromolecular imaging of leaf tissue using a multichannel focal plane array (FPA) infrared detector was compared with the proven method of infrared mapping with a synchrotron source, using transverse sections of leaves from a species of Eucalyptus. * A new histological method was developed, ideally suited to infrared spectroscopic analysis of leaf tissue. Spatial resolution and the signal-to-noise ratio of the FPA imaging and synchrotron mapping methods were compared. * An area of tissue 350 microm(2) required approx. 8 h to map using the synchrotron technique and approx. 2 min to image using the FPA. The two methods produced similar infrared images, which differentiated all tissue types in the leaves according to their macromolecular chemistry. * The synchrotron and FPA methods produced similar results, with the synchrotron method having superior signal-to-noise ratio and potentially better spatial resolution, whereas the FPA method had the advantage in terms of data acquisition time, expense and ease of use. FPA imaging offers a convenient, laboratory-based approach to microscopic chemical imaging of leaves.

Intercolonial variability in macromolecular composition in P-starved and P-replete Scenedesmus populations revealed by infrared microspectroscopy

Publisher: Wiley

Date: 10-2008

DOI: 10.1111/J.1529-8817.2008.00564.X

Abstract: Macromolecular variability in microalgal populations subject to different nutrient environments was investigated, using the chlorophyte alga Scenedesmus quadricauda (Turpin) Bréb. as a model organism. The large size of the four-cell coenobia in the strain used in this study (∼35 μm diameter) conveniently allowed high quality spectra to be obtained from in idual coenobia using a laboratory-based Fourier transform infrared (FTIR) microscope with a conventional globar source of IR. By drawing sizable subpopulations of coenobia from two Scenedesmus cultures grown under either nutrient-replete or P-starved conditions, the population variability in macromolecular composition, and the effects of nutrient change upon this, could be estimated. On average, P-starved coenobia had higher carbohydrate and lower protein absorbance compared with P-replete coenobia. These parameters varied between coenobia with histograms of the ratio of absorbance of the largest protein and carbohydrate bands being Gaussian distributed. Distributions for the P-replete and P-starved subpopulations were nonoverlapping, with the difference in mean ratios for the two populations being statistically significant. Greater variance was observed in the P-starved subpopulation. In addition, multivariate models were developed using the spectral data, which could accurately predict the nutrient status of an independent in idual coenobium, based on its FTIR spectrum. Partial least squares discriminant analysis (PLS-DA) was a better prediction method compared with soft independent modeling by class analogy (SIMCA).

Multimodal detection and analysis of a new type of advanced Heinz body-like aggregate (AHBA) and cytoskeleton deformation in human RBCs

Publisher: Royal Society of Chemistry (RSC)

Date: 2020

DOI: 10.1039/C9AN01707K

Abstract: A new type of aggregate, formed in human red blood cells (RBCs) in response to glutaraldehyde treatment, was discovered and analyzed with the classical and advanced biomolecular imaging techniques.

Effects of pre-processing of Raman spectra on in vivo classification of nutrient status of microalgal cells

Publisher: Wiley

Date: 05-2006

DOI: 10.1002/CEM.990

Infrared nanospectroscopic mapping of a single metaphase chromosome

Publisher: Oxford University Press (OUP)

Date: 25-07-2019

DOI: 10.1093/NAR/GKZ630

Abstract: The integrity of the chromatin structure is essential to every process occurring within eukaryotic nuclei. However, there are no reliable tools to decipher the molecular composition of metaphase chromosomes. Here, we have applied infrared nanospectroscopy (AFM-IR) to demonstrate molecular difference between eu- and heterochromatin and generate infrared maps of single metaphase chromosomes revealing detailed information on their molecular composition, with nanometric lateral spatial resolution. AFM-IR coupled with principal component analysis has confirmed that chromosome areas containing euchromatin and heterochromatin are distinguishable based on differences in the degree of methylation. AFM-IR distribution of eu- and heterochromatin was compared to standard fluorescent staining. We demonstrate the ability of our methodology to locate spatially the presence of anticancer drug sites in metaphase chromosomes and cellular nuclei. We show that the anticancer 'rule breaker' platinum compound [Pt[N(p-HC6F4)CH2]2py2] preferentially binds to heterochromatin, forming localized discrete foci due to condensation of DNA interacting with the drug. Given the importance of DNA methylation in the development of nearly all types of cancer, there is potential for infrared nanospectroscopy to be used to detect gene expression/suppression sites in the whole genome and to become an early screening tool for malignancy.

Determining the Age of Spoiled Milk from Dried Films Using Attenuated Reflection Fourier Transform Infrared (ATR FT-IR) Spectroscopy

Publisher: SAGE Publications

Date: 08-08-2019

DOI: 10.1177/0003702819842548

Abstract: Milk spoilage is an inevitable occurrence, which generates waste and can result in food poisoning. When milk spoils, the off-flavor and curdling are due to excessive proliferation of various bacteria which causes pH changes. Time, temperature, environment, and previous handling practice all affect the spoilage rate. There is a need for a fast reliable and accurate method that can identify in situ early spoilage of milk. Here we show the ability of attenuated total reflection Fourier transformed infrared spectroscopy (ATR FT-IR) in conjunction with multivariate data analysis to predict the age of milk. We found that dried films vastly increased the absorbance of important biomolecules within milk such as lipids, proteins, and sugars, compared to an unchanged milk s le. This allowed us to note the minor discrepancies that happened in spoilage. Spoilt milk was characterized by bands associated with increased lipids, proteins, and lactic acid and a decrease in carbohydrates. A semi-quantitative prediction model for milk spoilage at room temperature demonstrated ATR FT-IR spectroscopy can predict milk age with a root mean square error of prediction of approximately 14 h. The model showed poor performance in the first 40 h but the predictions improved significantly after this time. The experimental procedure proposed for detecting biomolecules within milk has the potential to improve common practice. Furthermore, the model would be a starting point for newer and improved methods to predict the spoilage date of milk, with potential commercial uses to reduce food waste and costs to the milk industry.

Spectral Pathology: general discussion

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6FD90011A

Fourier transform infrared microspectroscopy identifies early lineage commitment in differentiating human embryonic stem cells

Publisher: Elsevier BV

Date: 03-2010

DOI: 10.1016/J.SCR.2009.11.002

Abstract: Human ESCs (hESCs) are a valuable tool for the study of early human development and represent a source of normal differentiated cells for pharmaceutical and biotechnology applications and ultimately for cell replacement therapies. For all applications, it will be necessary to develop assays to validate the efficacy of hESC differentiation. We explored the capacity for FTIR spectroscopy, a technique that rapidly characterises cellular macromolecular composition, to discriminate mesendoderm or ectoderm committed cells from undifferentiated hESCs. Distinct infrared spectroscopic "signatures" readily distinguished hESCs from these early differentiated progeny, with bioinformatic models able to correctly classify over 97% of spectra. These data identify a role for FTIR spectroscopy as a new modality to complement conventional analyses of hESCs and their derivatives. FTIR spectroscopy has the potential to provide low-cost, automatable measurements for the quality control of stem and differentiated cells to be used in industry and regenerative medicine.

Editorial – the latest thinking and developments in optical diagnosis

Publisher: Royal Society of Chemistry (RSC)

Date: 2013

DOI: 10.1039/C3AN90052E

Raman acoustic levitation spectroscopy of red blood cells and Plasmodium falciparum trophozoites

Publisher: Royal Society of Chemistry (RSC)

Date: 2007

DOI: 10.1039/B706997A

Abstract: Methods to probe the molecular structure of living cells are of paramount importance in understanding drug interactions and environmental influences in these complex dynamical systems. The coupling of an acoustic levitation device with a micro-Raman spectrometer provides a direct molecular probe of cellular chemistry in a containerless environment minimizing signal attenuation and eliminating the affects of adhesion to walls and interfaces. We show that the Raman acoustic levitation spectroscopic (RALS) approach can be used to monitor the heme dynamics of a levitated 5 microL suspension of red blood cells and to detect hemozoin in malaria infected cells. The spectra obtained have an excellent signal-to-noise ratio and demonstrate for the first time the utility of the technique as a diagnostic and monitoring tool for minute s le volumes of living animal cells.

Vibrational Spectroscopic Based Approach for Diagnosing Babesia bovis Infection

Publisher: American Chemical Society (ACS)

Date: 06-2020

DOI: 10.1021/ACS.ANALCHEM.0C00150

Mechanism of hydrolysis of a platinum(IV) complex discovered by atomic telemetry

Publisher: Elsevier BV

Date: 10-2018

DOI: 10.1016/J.JINORGBIO.2018.07.012

Abstract: Herein we report on the hydrolysis mechanism of [Pt{N(p-HC

High‐resolution Raman imaging reveals spatial location of heme oxidation sites in single red blood cells of dried smears

Publisher: Wiley

Date: 09-10-2014

DOI: 10.1002/JRS.4600

Assessment of the statistical significance of classifications in infrared spectroscopy based diagnostic models

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4AN01783H

Abstract: Permutation testing in the evaluation of the statistical significance for infrared based classification of biological s les.

Diagnosing malaria infected cells at the single cell level using focal plane array Fourier transform infrared imaging spectroscopy

Publisher: Royal Society of Chemistry (RSC)

Date: 2014

DOI: 10.1039/C4AN00989D

Abstract: FTIR focal plane array imaging can be applied to diagnose single malaria infected cells in a thick film blood smear.

Synchrotron FTIR shows evidence of DNA damage and lipid accumulation in prostate adenocarcinoma PC-3 cells following proton irradiation

Publisher: Elsevier BV

Date: 09-2014

DOI: 10.1016/J.MOLSTRUC.2014.04.056

Quantification and Identification of Microproteinuria Using Ultrafiltration and ATR-FTIR Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 06-01-2020

DOI: 10.1021/ACS.ANALCHEM.9B03081

Abstract: The presence of low amounts of specific proteins in urine can be an indicator of diagnosis and prognosis of several diseases including renal failure and cancer. Hence, there is an urgent need for Point-of-care (PoC) methods, which can quantify microproteinuria levels (30-300 ppm) and identify the major proteins associated with the microproteinuria. In this study, we coupled ultracentrifugation with attenuated total reflectance-Fourier transform infrared (ATR-FTIR) to identify and quantify proteins in urine at low parts per million levels. The process involves the preconcentration of proteins from 500 μL of urine using an ultrafiltration device. After several washings, the isolated proteins are dried onto the ATR crystal forming a thin film. Imaging studies showed that the absorbance of the protein bands was linear with the amount of mass deposited on the crystal. The methodology was first evaluated with artificial urine spiked with 30-300 ppm of albumin. The calibration showed acceptable linearity (

Spectroscopic Studies on Photoinduced Reactions of the Anticancer Prodrug, trans,trans,trans‐[Pt(N₃)₂(OH)₂(py)₂]

Publisher: Wiley

Date: 05-02-2018

DOI: 10.1002/CHEM.201705349

Nanoscale Investigation into the Cellular Response of Glioblastoma Cells Exposed to Protons

Publisher: American Chemical Society (ACS)

Date: 25-05-2018

DOI: 10.1021/ACS.ANALCHEM.8B01497

Abstract: Exposure to ionizing radiation can induce cellular defense mechanisms including cell activation and rapid proliferation prior to metastasis and in extreme cases can result in cell death. Herewith we apply infrared nano- and microspectroscopy combined with multidimensional data analysis to characterize the effect of ionizing radiation on single glioblastoma nuclei isolated from cells treated with 10 Gy of X-rays or 1 and 10 Gy of protons. We observed chromatin fragmentation related to the formation of apoptotic bodies following X-ray exposure. Following proton irradiation we detected evidence of a DNA conformational change (B-DNA to A-DNA transition) related to DNA repair and accompanied by an increase in protein content related to the synthesis of peptide enzymes involved in DNA repair. We also show that proton exposure can increase cholesterol and sterol ester synthesis, which are important lipids involved in the metastatic process changing the fluidity of the cellular membrane in preparation for rapid proliferation.

Tip-Enhanced Raman Scattering (TERS) from Hemozoin Crystals within a Sectioned Erythrocyte

Publisher: American Chemical Society (ACS)

Date: 11-05-2011

DOI: 10.1021/NL103004N

Abstract: Tip-enhanced Raman scattering (TERS) is a powerful technique to obtain molecular information on a nanometer scale, however, the technique has been limited to cell surfaces, viruses, and isolated molecules. Here we show that TERS can be used to probe hemozoin crystals at less than 20 nm spatial resolution in the digestive vacuole of a sectioned malaria parasite-infected cell. The TERS spectra clearly show characteristic bands of hemozoin that can be correlated to a precise position on the crystal by comparison with the corresponding atomic force microscopy (AFM) image. These are the first recorded AFM images of hemozoin crystals inside malaria-infected cells and clearly show the hemozoin crystals protruding from the embedding medium. TERS spectra recorded of these crystals show spectral features consistent with a five-coordinate high-spin ferric heme complex, which include the electron density marker band ν(4) at 1373 cm(-1) and other porphyrin skeletal and ring breathing modes at approximately 1636, 1557, 1412, 1314, 1123, and 1066 cm(-1). These results demonstrate the potential of the AFM/TERS technique to obtain nanoscale molecular information within a sectioned single cell. We foresee this approach paving the way to a new independent drug screening modality for detection of drugs binding to the hemozoin surface within the digestive vacuole of the malaria trophozoite.

Resonance Raman spectroscopy can detect structural changes in haemozoin (malaria pigment) following incubation with chloroquine in infected erythrocytes

Publisher: Wiley

Date: 04-03-2008

DOI: 10.1016/J.FEBSLET.2008.02.062

Abstract: Resonance Raman spectroscopy was applied to monitor the effects of chloroquine (CQ) treatment on cultures of Plasmodium falciparum trophozoites. A number of bands assigned to A(1g) and B(1g) modes characteristic of the haemozoin aggregate are reduced in intensity in the CQ-treated cells, however, no bands from the CQ are observed. The intensity changes are attributed to intermolecular drug binding of the CQ in a sandwich type complex between ferriprotoporphyrin IX (FePPIX) dimer units. It is postulated that the CQ binds via pi-pi interactions between adjacent and orientated porphyrins thereby disrupting the haemozoin aggregate and reducing excitonic interactions between adjacent haems. The results show the potential of Raman microscopy as a screening tool for FePPIX:drug interactions in live cells.

The application of ATR-FTIR Spectroscopy and the Reversible DNA Conformation as a Sensor to Test the Effectiveness of Platinum(II) Anticancer Drugs

Publisher: MDPI AG

Date: 18-10-2018

DOI: 10.20944/PREPRINTS201810.0406.V1

Abstract: Platinum(II) complexes have been found to be effective against cancer cells. Cisplatin curbs cell replication by interacting with the deoxyribonucleic acid (DNA), eventually leading to cell death and reducing cell proliferation. In order to investigate the ability of platinum complexes to affect cancer cells, two ex les from the class of polyflurophenylorganoamidoplatinum(II) complexes were synthesised and tested on isolated DNA. The two compounds trans-[N,N& rsquo -bis(1,2,3,5,6-pentafluorophenyl)ethane-1,2-diaminato(1-)](2,3,4,5,6-pentafluorobenzoato)(pyridine)platinum(II) (PFB), and trans-[N,N& rsquo -bis(1,2,3,5,6-pentafluorophenyl)ethane-1,2-diaminato(1-)](2,4,6-trimethylbenzoato)(pyridine)platinum(II) (TMB) were compared with cisplatin through their reaction with DNA. Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy was applied to analyse the interaction of the Pt(II) complexes with DNA in the hydrated, dehydrated and rehydrated state. These were compared with control DNA in acetone/water (PFB, TMB) and isotonic saline (cisplatin) under the same conditions. Principle Component Analysis (PCA) was applied to compare the ATR-FTIR spectra of the untreated control DNA with spectra of PFB and TMB treated DNA s les. Disruptions in the conformation of DNA treated with the Pt(II) complexes upon rehydration were mainly observed by monitoring the position of the IR-band around 1711 cm-1 assigned to the DNA base-stacking vibration. Furthermore, other intensity changes in the phosphodiester bands of DNA at ~1234 cm-1 and 1225 cm-1 and shifts in the dianionic phosphodiester vibration at 966 cm-1 were observed. The isolated double stranded DNA (dsDNA) or single stranded DNA (ssDNA) showed different structural changes when incubated with the studied compounds. PCA confirmed PFB had the most dramatic effect by denaturing both dsDNA and ssDNA. Both compounds, along with cisplatin, induced changes in DNA bands at 1711, 1088, 1051 and 966 cm-1 indicative of DNA conformation changes. The ability to monitor conformational change with infrared spectroscopy paves the way for a sensor to screen for new anticancer therapeutic agents.

Detection of an en masse and reversible B- to A-DNA conformational transition in prokaryotes in response to desiccation

Publisher: The Royal Society

Date: 06-08-2014

DOI: 10.1098/RSIF.2014.0454

Abstract: The role that DNA conformation plays in the biochemistry of cells has been the subject of intensive research since DNA polymorphism was discovered. B-DNA has long been considered the native form of DNA in cells although alternative conformations of DNA are thought to occur transiently and along short tracts. Here, we report the first direct observation of a fully reversible en masse conformational transition between B- and A-DNA within live bacterial cells using Fourier transform infrared (FTIR) spectroscopy. This biospectroscopic technique allows for non-invasive and reagent-free examination of the holistic biochemistry of s les. For this reason, we have been able to observe the previously unknown conformational transition in all four species of bacteria investigated. Detection of this transition is evidence of a previously unexplored biological significance for A-DNA and highlights the need for new research into the role that A-DNA plays as a cellular defence mechanism and in stabilizing the DNA conformation. Such studies are pivotal in understanding the role of A-DNA in the evolutionary pathway of nucleic acids. Furthermore, this discovery demonstrates the exquisite capabilities of FTIR spectroscopy and opens the door for further investigations of cell biochemistry with this under-used technique.

In situ SERS probing of nano-silver coated individual yeast cells

Publisher: Elsevier BV

Date: 11-2013

DOI: 10.1016/J.BIOS.2013.05.053

Abstract: For understanding cells functionalities and their communications, there is a need for highly sensitive cell analysis platforms capable of assessing non-specific chemicals on the surface and in the vicinity of cells. We report a microfluidic system integrating dielectrophoresis and surface enhanced Raman scattering (SERS) for the trapping and real time monitoring of cell functions in isolated and grouped cell clusters. Yeast cells are coated with silver nanoparticles to enable highly sensitive SERS analysis. The SERS responses of cells are examined under various conditions: live vs. dead and isolated vs. grouped. This work illustrates the feasibility of the system for in situ cell monitoring and analysis of secreted chemicals during their growth, metabolism, proliferation and apoptosis.

Transfer time to a specialist burn service and influence on burn mortality in Australia and New Zealand: A multi-centre, hospital based retrospective cohort study

Publisher: Elsevier BV

Date: 06-2015

DOI: 10.1016/J.BURNS.2015.01.016

Abstract: In Australia and New Zealand (ANZ), health care is provided for ∼26 million people dispersed across the eight million square kilometres of the two countries. Providing optimal care prior to and during transfer across such vast distances is challenging. Lengthening the time taken to definitive burn care has a negative impact on burn outcome. The aims of this study were to determine if transfer time and admission pathway influenced burn mortality and to identify the factors predicting burn mortality in ANZ. The study included all adult burn patient admission data from 15 of 17 burn services submitted to the Australian and New Zealand Burn Association bi-national registry (2010-2012). Multivariate logistic regression analyses were conducted to address the study aims. Of the 2892 patients, 69 (2.4%) died following burn. Time to admission and direct admission to a burn centre did not independently influence burn mortality except when patients with inhalation injury took >16 h to transfer to definitive care. The risk of death was increased 5.7 times in the presence of inhalation injury. Burn size and age lified the risk of death while gender did not. In ANZ, pre-hospital transport systems and peripheral hospital stabilisation were not associated with an increased risk of death due to burn except when inhalation injury was present. The results of this study indicate that burn patients with inhalation injury should be stabilised and transferred to a burn service within 16 h of burn.

Single cell analysis/data handling: general discussion

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C6FD90012G

Label-Free Non-Destructive Identification of Stem Cells in the Hair Follicle with Confocal Raman Spectrocopy

Publisher: AIP

Date: 2010

DOI: 10.1063/1.3482558

Red Blood Cells Polarize Green Laser Light Revealing Hemoglobin′s Enhanced Non‐Fundamental Raman Modes

Publisher: Wiley

Date: 26-09-2014

DOI: 10.1002/CPHC.201402598

Direct Nanospectroscopic Verification of the Amyloid Aggregation Pathway

Publisher: Wiley

Date: 06-06-2018

DOI: 10.1002/ANIE.201803234

Abstract: The aggregation pathways of neurodegenerative peptides determine the disease etiology, and their better understanding can lead to strategies for early disease treatment. Previous research has allowed modelling of hypothetic aggregation pathways. However, their direct experimental observation has been elusive owing to methodological limitations. Herein, we demonstrate that nanoscale chemical mapping by tip-enhanced Raman spectroscopy of single amyloid fibrils at various stages of aggregation captures the fibril formation process. We identify changes in TERS/Raman marker bands for Aβ

Bio-sensing with butterfly wings: naturally occurring nano-structures for SERS-based malaria parasite detection

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4CP04930F

Abstract: A gold-coated butterfly wing is used as a SERS substrate to diagnose malaria based on intense scattering from hemozoin aggregates.

Correction: Synchrotron macro ATR-FTIR microspectroscopy for high-resolution chemical mapping of single cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1AN90049H

Abstract: Correction for ‘Synchrotron macro ATR-FTIR microspectroscopy for high-resolution chemical mapping of single cells’ by Jitraporn Vongsvivut et al. , Analyst , 2019, 144 , 3226–3238, DOI: 10.1039/C8AN01543K.

Micro-Raman characterisation of the R to T state transition of haemoglobin within a single living erythrocyte

Publisher: Elsevier BV

Date: 05-2001

DOI: 10.1016/S0167-4889(01)00089-1

Abstract: We present the first recorded Raman spectra of haemoglobin in both the R and T states from within a single living erythrocyte using 632.8 nm excitation. Bands characteristic of low spin haems are observed in oxygenated and carboxylated erythrocytes at approx. 1636 (nu(10)), 1562-1565 (nu(2)), 1250-1245 cm(-1) (nu(13)) and 1226-1224 cm(-1) (nu(5)+nu(8)). The spectra of deoxygenated and methaemoglobin erythrocytes have characteristic high spin bands at approx. 1610-1606 cm(-1) (nu(10)), 1582-1580 (nu(37)), 1547-1544 (nu(11)), 1230-1220 cm(-1) (nu(13)) and 1215-1210 cm(-1) (nu(5)+nu(8)). Bands at 1172 (nu(30)), 976 (nu(45)) and 672 (nu(7)) cm(-1) appear to be enhanced at 632.8 nm in low spin haems. The oxidation state marker band (nu(4)) at 1364-1366 cm(-1) appeared invariant within this domain in all single cells and conditions investigated contrary to other resonance Raman studies on haem isolates. The information gained by in vivo single erythrocyte molecular analysis has important ramifications to the understanding of fundamental physiological processes and may have applications in the diagnosis and treatment of red blood cell disorders.

Infrared Based Saliva Screening Test for COVID‐19

Publisher: Wiley

Date: 29-06-2021

DOI: 10.1002/ANIE.202104453

Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has resulted in an unprecedented need for diagnostic testing that is critical in controlling the spread of COVID‐19. We propose a portable infrared spectrometer with purpose‐built transflection accessory for rapid point‐of‐care detection of COVID‐19 markers in saliva. Initially, purified virion particles were characterized with Raman spectroscopy, synchrotron infrared (IR) and AFM‐IR. A data set comprising 171 transflection infrared spectra from 29 subjects testing positive for SARS‐CoV‐2 by RT‐qPCR and 28 testing negative, was modeled using Monte Carlo Double Cross Validation with 50 randomized test and model sets. The testing sensitivity was 93 % (27/29) with a specificity of 82 % (23/28) that included positive s les on the limit of detection for RT‐qPCR. Herein, we demonstrate a proof‐of‐concept high throughput infrared COVID‐19 test that is rapid, inexpensive, portable and utilizes s le self‐collection thus minimizing the risk to healthcare workers and ideally suited to mass screening.

Spectroscopic Studies on Photoinduced Reactions of the Anticancer Prodrug, trans,trans,trans‐[Pt(N₃)₂(OH)₂(py)₂]

Publisher: Wiley

Date: 08-02-2018

DOI: 10.1002/CHEM.201800162

Front Cover: Spectroscopic Studies on Photoinduced Reactions of the Anticancer Prodrug, trans,trans,trans‐[Pt(N₃)₂(OH)₂(py)₂] (Chem. Eur. J. 22/2018)

Publisher: Wiley

Date: 08-02-2018

DOI: 10.1002/CHEM.201800161

SR-FTIR Coupled with Principal Component Analysis Shows Evidence for the Cellular Bystander Effect

Publisher: Radiation Research Society

Date: 07-2015

DOI: 10.1667/RR13798.1

High‐resolution Raman imaging reveals spatial location of heme oxidation sites in single red blood cells of dried smears

Publisher: Wiley

Date: 17-12-2015

DOI: 10.1002/JRS.4869

Assessment of discriminant models in infrared imaging using constrained repeated random sampling – Cross validation

Publisher: Elsevier BV

Date: 11-2018

DOI: 10.1016/J.ACA.2018.05.019

Abstract: Infrared (IR) imaging is an emerging and powerful approach for studying the molecular composition of cells and tissues. It is a non-destructive and phenotypic technique which combines label-free molecular specific information from cells and tissues provided by IR with spatial resolution, offering great potential in biochemical and biomedical research and routine applications. The application of multivariate discriminant analysis using bilinear models such as Partial Least Squares-Discriminant Analysis (PLS-DA) to IR images requires to unfold the spatial directions in a two-way matrix, resulting in a loss of spatial information and structure. In this article, first we evidence that internal validation methods such as repeated k-fold cross-validation (CV) can be overly optimistic when the pixel size of the image is lower than the lateral spatial resolution. Secondly, we propose a new approach for the unbiased internal evaluation of the model performance named COnstrained Repeated Random Subs ling-Cross Validation (CORRS-CV). This method is based on the generation of q training and test sub-sets using a constrained random s ling of n training pixels without replacement and it circumvents overly optimistic effects due to overs ling, providing more accurate and robust images. The approach can be applied in IR microscopy for the development of discriminant models to analyse underlying biochemical differences associated to anatomical and histopathological features in cells and tissues.

Elucidation of Interaction between Metal-Free Tetraphenylporphine and Surface Ag Atoms through Temporal Fluctuation of Surface-Enhanced Resonance Raman Scattering and Background-Light Emission

Publisher: American Chemical Society (ACS)

Date: 25-04-2006

DOI: 10.1021/JP0609939

Abstract: We have observed simultaneously temporal fluctuation of surface-enhanced resonance Raman scattering (SERRS) and its background-light emission from single Ag nanoaggregates that were adsorbed with metal-free tetraphenylporphine (H(2)TPP) molecules. We found that temporally stable SERRS spectra showed clearly a SERRS band that is attributed to a stretching mode of a chemical bond between a carbon atom and a non-hydrogenated nitrogen atom (C(alpha)-N). This stretching mode was not observed in regular resonance Raman spectra which are free from surface enhancement. On the other hand, we also found that temporally unstable SERRS spectra did not clearly show a C(alpha)-N stretching mode in SERRS bands. Furthermore, temporally stable SERRS spectra were accompanied by temporally stable background-light emission. Kobayashi et al. [J. Phys. Chem. 1985, 89, 5174] reported that formation of an Ag-N bond between surface Ag atoms and non-hydrogenated N atoms in a pyrrole ring enhances the intensity of a C(alpha)-N stretching mode. Thus, the observed relationship between clear appearance of a C(alpha)-N stretching mode and temporal stability of SERRS plus background-light emission strongly suggests that formation of a stable Ag-N bond suppresses fluctuation of both SERRS and background-light emission. Furthermore, the observed relationship implies that chemical contribution to SERRS is stabilization of H(2)TPP molecules that are adsorbed on SERRS-active sites by formation of Ag-N bonds. Additionally, we attributed background-light emission to luminescence of complexes between H(2)TPP molecules and surface Ag atoms considering possible formation of Ag-N bonds, synchronized SERRS intensity with background-light emission intensity, blue-shifted background-light emission maxima from normal fluorescence maxima, and previous reports related to electronic structures of H(2)TPP molecules on Ag surfaces.

Infrared imaging of normal and diseased cervical tissue sections

Publisher: SPIE

Date: 16-02-2005

DOI: 10.1117/12.582294

Linearly Polarized Infrared Spectroscopy for the Analysis of Biological Materials

Publisher: SAGE Publications

Date: 19-07-2023

DOI: 10.1177/00037028231180233

Abstract: The analysis of biological s les with polarized infrared spectroscopy (p-IR) has long been a widely practiced method for the determination of s le orientation and structural properties. In contrast to earlier works, which employed this method to investigate the fundamental chemistry of biological systems, recent interests are moving toward “real-world” applications for the evaluation and diagnosis of pathological states. This focal point review provides an up-to-date synopsis of the knowledge of biological materials garnered through linearly p-IR on biomolecules, cells, and tissues. An overview of the theory with special consideration to biological s les is provided. Different modalities which can be employed along with their capabilities and limitations are outlined. Furthermore, an in-depth discussion of factors regarding s le preparation, s le properties, and instrumentation, which can affect p-IR analysis is provided. Additionally, attention is drawn to the potential impacts of analysis of biological s les with inherently polarized light sources, such as synchrotron light and quantum cascade lasers. The vast applications of p-IR for the determination of the structure and orientation of biological s les are given. In conclusion, with considerations to emerging instrumentation, findings by other techniques, and the shift of focus toward clinical applications, we speculate on the future directions of this methodology.

ICE: a new method for the multivariate curve resolution of hyperspectral images

Publisher: Wiley

Date: 02-2009

DOI: 10.1002/CEM.1198

A Near-Infrared “Matchbox Size” Spectrometer to Detect and Quantify Malaria Parasitemia

Publisher: American Chemical Society (ACS)

Date: 24-03-2021

DOI: 10.1021/ACS.ANALCHEM.0C05103

A portable Raman acoustic levitation spectroscopic system for the identification and environmental monitoring of algal cells

Publisher: American Chemical Society (ACS)

Date: 21-06-2005

DOI: 10.1021/AC050281Z

Abstract: We report the coupling of a portable Raman spectrometer to an acoustic levitation device to enable environmental monitoring and the potential taxonomic identification of microalgae. Spectra of living cells were recorded at 785 nm using a fiber-optic probe coupled to a portable Raman spectrometer. The spectra exhibit an excellent signal-to-noise ratio and clearly show bands from chlorophyll a and beta-carotene. Spectra of levitated photobleached microalgae clearly show a reduction in chlorophyll a concentration relative to beta-carotene after 10 min of exposure to a quartz halogen l . Spectra recorded from levitated nitrogen-limited cells also show a significant reduction in bands associated with chlorophyll a, as compared to nitrogen-replete cells. To investigate the diagnostic capability of the technique, four species of microalgae were analyzed. Good quality spectra of all four species were obtained showing varying ratios of beta-carotene to chlorophyll. The combination of an acoustic levitation device and a portable Raman spectrometer shows potential as a taxonomic and environmental monitoring tool with direct application to field studies in remote environments.

The importance of hydration and DNA conformation in interpreting infrared spectra of cells and tissues

Publisher: Royal Society of Chemistry (RSC)

Date: 2016

DOI: 10.1039/C5CS00511F

Abstract: The effect of hydration on cells and tissues modifies the DNA conformation leading to dramatic changes in the FTIR spectra, which has important implications in disease diagnosis.

Multispectral Atomic Force Microscopy-Infrared Nano-Imaging of Malaria Infected Red Blood Cells

Publisher: American Chemical Society (ACS)

Date: 12-01-2018

DOI: 10.1021/ACS.ANALCHEM.7B04318

Abstract: Atomic force microscopy-infrared (AFM-IR) spectroscopy is a powerful new technique that can be applied to study molecular composition of cells and tissues at the nanoscale. AFM-IR maps are acquired using a single wavenumber value: they show either the absorbance plotted against a single wavenumber value or a ratio of two absorbance values. Here, we implement multivariate image analysis to generate multivariate AFM-IR maps and use this approach to resolve subcellular structural information in red blood cells infected with Plasmodium falciparum at different stages of development. This was achieved by converting the discrete spectral points into a multispectral line spectrum prior to multivariate image reconstruction. The approach was used to generate compositional maps of subcellular structures in the parasites, including the food vacuole, lipid inclusions, and the nucleus, on the basis of the intensity of hemozoin, hemoglobin, lipid, and DNA IR marker bands, respectively. Confocal Raman spectroscopy was used to validate the presence of hemozoin in the regions identified by the AFM-IR technique. The high spatial resolution of AFM-IR combined with hyperspectral modeling enables the direct detection of subcellular components, without the need for cell sectioning or immunological/biochemical staining. Multispectral-AFM-IR thus has the capacity to probe the phenotype of the malaria parasite during its intraerythrocytic development. This enables novel approaches to studying the mode of action of antimalarial drugs and the phenotypes of drug-resistant parasites, thus contributing to the development of diagnostic and control measures.

A resonance Raman spectroscopic investigation into the effects of fixation and dehydration on heme environment of hemoglobin

Publisher: Wiley

Date: 11-05-2009

DOI: 10.1002/JRS.2317

Near-infrared autofluorescence induced by intraplaque hemorrhage and heme degradation as marker for high-risk atherosclerotic plaques

Publisher: Springer Science and Business Media LLC

Date: 13-07-2017

DOI: 10.1038/S41467-017-00138-X

Abstract: Atherosclerosis is a major cause of mortality and morbidity, which is mainly driven by complications such as myocardial infarction and stroke. These complications are caused by thrombotic arterial occlusion localized at the site of high-risk atherosclerotic plaques, of which early detection and therapeutic stabilization are urgently needed. Here we show that near-infrared autofluorescence is associated with the presence of intraplaque hemorrhage and heme degradation products, particularly bilirubin by using our recently created mouse model, which uniquely reflects plaque instability as seen in humans, and human carotid endarterectomy s les. Fluorescence emission computed tomography detecting near-infrared autofluorescence allows in vivo monitoring of intraplaque hemorrhage, establishing a preclinical technology to assess and monitor plaque instability and thereby test potential plaque-stabilizing drugs. We suggest that near-infrared autofluorescence imaging is a novel technology that allows identification of atherosclerotic plaques with intraplaque hemorrhage and ultimately holds promise for detection of high-risk plaques in patients.

Light Scattering By Optically-Trapped Vesicles Affords Unprecedented Temporal Resolution Of Lipid-Raft Dynamics

Publisher: Springer Science and Business Media LLC

Date: 17-08-2017

DOI: 10.1038/S41598-017-08980-1

Abstract: A spectroscopic technique is presented that is able to identify rapid changes in the bending modulus and fluidity of vesicle lipid bilayers on the micrometer scale, and distinguish between the presence and absence of heterogeneities in lipid-packing order. In idual unilamellar vesicles have been isolated using laser tweezers and, by measuring the intensity modulation of elastic back-scattered light, changes in the biophysical properties of lipid bilayers were revealed. Our approach offers unprecedented temporal resolution and, uniquely, physical transformations of lipid bilayers can be monitored on a length scale of micrometers. As an ex le, the deformation of a membrane bilayer following the gel-to-fluid phase transition in a pure phospholipid vesicle was observed to take place across an interval of 54 ± 5 ms corresponding to an estimated full-width of only ~1 m°C. Dynamic heterogeneities in packing order were detected in mixed-lipid bilayers. Using a ternary mixture of lipids, the modulated-intensity profile of elastic back-scattered light from an optically-trapped vesicle revealed an abrupt change in the bending modulus of the bilayer which could be associated with the dissolution of ordered microdomains ( i.e ., lipid rafts). This occurred across an interval of 30 ± 5 ms (equivalent to ~1 m°C).

Observing the cyclical changes in cervical epithelium using infrared microspectroscopy

Publisher: Elsevier BV

Date: 02-2002

DOI: 10.1016/S0924-2031(01)00155-2

An attenuated total reflection (ATR) and Raman spectroscopic investigation into the effects of chloroquine on Plasmodium falciparum-infected red blood cells

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4AN01904K

Abstract: Attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) and Raman spectroscopy were used to compare chloroquine (CQ)-treated and untreated cultured Plasmodium falciparum -infected human red blood cells (iRBCs).

Spectroscopy goes viral: Diagnosis of hepatitis B and C virus infection from human sera using ATR-FTIR spectroscopy

Publisher: Elsevier BV

Date: 12-2019

DOI: 10.1016/J.CLISPE.2020.100001

Single cell assessment of yeast metabolic engineering for enhanced lipid production using Raman and AFM-IR imaging

Publisher: Springer Science and Business Media LLC

Date: 10-04-2018

DOI: 10.1186/S13068-018-1108-X

Characterising nutrient-induced fluorescence transients (NIFTs) in nitrogen-stressed Chlorella emersonii (Chlorophyta)

Publisher: Informa UK Limited

Date: 04-09-2007

DOI: 10.2216/06-55.1

Resonance Raman spectroscopy provides evidence of heme ordering within the functional erythrocyte

Publisher: Elsevier BV

Date: 07-2005

DOI: 10.1016/J.VIBSPEC.2005.02.016

Resonance Raman spectroscopy in malaria research

Publisher: Informa UK Limited

Date: 10-2006

DOI: 10.1586/14789450.3.5.525

Abstract: In recent years, the field of Raman spectroscopy has witnessed a surge in technological development, with the incorporation of ultrasensitive, charge-coupled devices, improved laser sources and precision Rayleigh-filter systems. This has led to the development of sensitive confocal micro-Raman spectrometers and imaging spectrometers that are capable of obtaining high spatial-resolution spectra and images of subcellular components within single living cells. This review reports on the application of resonance micro-Raman spectroscopy to the study of malaria pigment (hemozoin), a by-product of hemoglobin catabolization by the malaria parasite, which is an important target site for antimalarial drugs. The review aims to briefly describe recent studies on the application of this technology, elucidate molecular and electronic properties of the malaria pigment and its synthetic analog beta-hematin, provide insight into the mechanism of hemozoin formation within the food vacuole of the parasite, and comment on developing strategies for using this technology in drug-screening protocols.

Infrared Spectroscopy of Blood

Publisher: SAGE Publications

Date: 28-01-2021

DOI: 10.1177/0003702820985856

Abstract: The magnitude of infectious diseases in the twenty-first century created an urgent need for point-of-care diagnostics. Critical shortages in reagents and testing kits have had a large impact on the ability to test patients with a suspected parasitic, bacteria, fungal, and viral infections. New point-of-care tests need to be highly sensitive, specific, and easy to use and provide results in rapid time. Infrared spectroscopy, coupled to multivariate and machine learning algorithms, has the potential to meet this unmet demand requiring minimal s le preparation to detect both pathogenic infectious agents and chronic disease markers in blood. This focal point article will highlight the application of Fourier transform infrared spectroscopy to detect disease markers in blood focusing principally on parasites, bacteria, viruses, cancer markers, and important analytes indicative of disease. Methodologies and state-of-the-art approaches will be reported and potential confounding variables in blood analysis identified. The article provides an up to date review of the literature on blood diagnosis using infrared spectroscopy highlighting the recent advances in this burgeoning field.

A Combined Near-Infrared and Mid-Infrared Spectroscopic Approach for the Detection and Quantification of Glycine in Human Serum

Publisher: MDPI AG

Date: 15-06-2022

DOI: 10.3390/S22124528

Abstract: Serum is an important candidate in proteomics analysis as it potentially carries key markers on health status and disease progression. However, several important diagnostic markers found in the circulatory proteome and the low-molecular-weight (LMW) peptidome have become analytically challenging due to the high dynamic concentration range of the constituent protein eptide species in serum. Herein, we propose a novel approach to improve the limit of detection (LoD) of LMW amino acids by combining mid-IR (MIR) and near-IR spectroscopic data using glycine as a model LMW analyte. This is the first ex le of near-IR spectroscopy applied to elucidate the detection limit of LMW components in serum moreover, it is the first study of its kind to combine mid-infrared (25–2.5 μm) and near-infrared (2500–800 nm) to detect an analyte in serum. First, we evaluated the prediction model performance in idually with MIR (ATR-FTIR) and NIR spectroscopic methods using partial least squares regression (PLS-R) analysis. The LoD was found to be 0.26 mg/mL with ATR spectroscopy and 0.22 mg/mL with NIR spectroscopy. Secondly, we examined the ability of combined spectral regions to enhance the detection limit of serum-based LMW amino acids. Supervised extended wavelength PLS-R resulted in a root mean square error of prediction (RMSEP) value of 0.303 mg/mL and R2 value of 0.999 over a concentration range of 0–50 mg/mL for glycine spiked in whole serum. The LoD improved to 0.17 mg/mL from 0.26 mg/mL. Thus, the combination of NIR and mid-IR spectroscopy can improve the limit of detection for an LMW compound in a complex serum matrix.

Simultaneous ATR-FTIR Based Determination of Malaria Parasitemia, Glucose and Urea in Whole Blood Dried onto a Glass Slide.

Publisher: American Chemical Society (ACS)

Date: 28-04-2017

DOI: 10.1021/ACS.ANALCHEM.6B04578

Abstract: New diagnostic tools that can detect malaria parasites in conjunction with other diagnostic parameters are urgently required. In this study, Attenuated Total Reflection Fourier transform infrared (ATR-FTIR) spectroscopy in combination with Partial Least Square Discriminant Analysis (PLS-DA) and Partial Least Square Regression (PLS-R) have been applied as a point-of-care test for identifying malaria parasites, blood glucose, and urea levels in whole blood s les from thick blood films on glass slides. The specificity for the PLS-DA was found to be 98% for parasitemia levels >0.5%, but a rather low sensitivity of 70% was achieved because of the small number of negative s les in the model. In PLS-R the Root Mean Square Error of Cross Validation (RMSECV) for parasite concentration (0-5%) was 0.58%. Similarly, for glucose (0-400 mg/dL) and urea (0-250 mg/dL) spiked s les, relative RMSECVs were 16% and 17%, respectively. The method reported here is the first ex le of multianalyte/disease diagnosis using ATR-FTIR spectroscopy, which in this case, enabled the simultaneous quantification of glucose and urea analytes along with malaria parasitemia quantification using one spectrum obtained from a single drop of blood on a glass microscope slide.

Spectroscopic analysis of myoglobin and cytochrome c dynamics in isolated cardiomyocytes during hypoxia and reoxygenation

Publisher: The Royal Society

Date: 04-2015

DOI: 10.1098/RSIF.2014.1339

Abstract: Raman microspectroscopy was applied to monitor the intracellular redox state of myoglobin and cytochrome c from isolated adult rat cardiomyocytes during hypoxia and reoxygenation. The nitrite reductase activity of myoglobin leads to the production of nitric oxide in cells under hypoxic conditions, which is linked to the inhibition of mitochondrial respiration. In this work, the subsequent reoxygenation of cells after hypoxia is shown to lead to increased levels of oxygen-bound myoglobin relative to the initial levels observed under normoxic conditions. Increased levels of reduced cytochrome c in ex vivo cells are also observed during hypoxia and reoxygenation by Raman microspectroscopy. The cellular response to reoxygenation differed dramatically depending on the method used in the preceding step to create hypoxic conditions in the cell suspension, where a chemical agent, sodium dithionite, leads to reduction of cytochromes in addition to removal of dissolved oxygen, and bubbling-N 2 gas leads to displacement of dissolved oxygen only. These results have an impact on the assessment of experimental simulations of hypoxia in cells. The spectroscopic technique employed in this work will be used in the future as an analytical method to monitor the effects of varying levels of oxygen and nutrients supplied to cardiomyocytes during either the preconditioning of cells or the reperfusion of ischaemic tissue.

Raman spectroscopy as a tool for tracking cyclopropane fatty acids in genetically engineeredSaccharomyces cerevisiae

Publisher: Royal Society of Chemistry (RSC)

Date: 2019

DOI: 10.1039/C8AN01477A

Abstract: We demonstrate the first spectrum of cyclopropane fatty acid and track its presence in yeast using Raman spectroscopy and PLS-DA.

Correction: Empirical study on the effects of acquisition parameters for FTIR hyperspectral imaging of brain tissue

Publisher: Royal Society of Chemistry (RSC)

Date: 2021

DOI: 10.1039/D1AY90074A

Abstract: Correction for ‘Empirical study on the effects of acquisition parameters for FTIR hyperspectral imaging of brain tissue’ by J. Sacharz et al. , Anal. Methods , 2020, 12 , 4334–4342, DOI: 10.1039/C9AY01200A.

Vibrational Spectroscopy as a Sensitive Probe for the Chemistry of Intra-Phase Bacterial Growth

Publisher: MDPI AG

Date: 18-06-2020

DOI: 10.3390/S20123452

Abstract: Bacterial growth in batch cultures occurs in four phases (lag, exponential/log, stationary and death phase) that differ distinctly in number of different bacteria, biochemistry and physiology. Knowledge regarding the growth phase and its kinetics is essential for bacterial research, especially in taxonomic identification and monitoring drug interactions. However, the conventional methods by which to assess microbial growth are based only on cell counting or optical density, without any insight into the biochemistry of cells or processes. Both Raman and Fourier transform infrared (FTIR) spectroscopy have shown potential to determine the chemical changes occurring between different bacterial growth phases. Here, we extend the application of spectroscopy and for the first time combine both Raman and FTIR microscopy in a multimodal approach to detect changes in the chemical compositions of bacteria within the same phase (intra-phase). We found a number of spectral markers associated with nucleic acids (IR: 964, 1082, 1215 cm−1 RS: 785, 1483 cm−1), carbohydrates (IR: 1035 cm−1 RS: 1047 cm−1) and proteins (1394 cm−1, amide II) reflecting not only inter-, but also intra-phase changes in bacterial chemistry. Principal component analysis performed simultaneously on FTIR and Raman spectra enabled a clear-cut, time-dependent discrimination between intra-lag phase bacteria probed every 30 min. This demonstrates the unique capability of multimodal vibrational spectroscopy to probe the chemistry of bacterial growth even at the intra-phase level, which is particularly important for the lag phase, where low bacterial numbers limit conventional analytical approaches.

Monitoring the Progression of Liver Fluke-Induced Cholangiocarcinoma in a Hamster Model Using Synchrotron FTIR Microspectroscopy and Focal Plane Array Infrared Imaging

Publisher: American Chemical Society (ACS)

Date: 10-11-2020

DOI: 10.1021/ACS.ANALCHEM.0C02656

Front Cover: Near‐Infrared Spectroscopic Characterization of Cardiac and Renal Fibrosis in Fixed and Fresh Rat Tissue (Anal. Sens. 1/2023)

Publisher: Wiley

Date: 12-12-2023

DOI: 10.1002/ANSE.202200105

Near‐Infrared Spectroscopic Characterization of Cardiac and Renal Fibrosis in Fixed and Fresh Rat Tissue

Publisher: Wiley

Date: 13-12-2023

DOI: 10.1002/ANSE.202200106

Abstract: Invited for this month‘s cover are the collaborating group(s) of Center for Biospectroscopy at Monash University and Austin Health at the University of Melbourne, University of Eastern Finland and the University of Queensland. The cover‐art shows a handheld near‐infrared spectroscopic probe to detect fibrosis in real time using a murine model. More information can be found in the Research Article by John A. Adegoke, Jaishankar Raman, Bayden R. Wood, and co‐workers .

Rapid Approach for Detection of Antibiotic Resistance in Bacteria Using Vibrational Spectroscopy

Publisher: American Chemical Society (ACS)

Date: 14-05-2020

DOI: 10.1021/ACS.ANALCHEM.0C00474

Early detection of the chemical changes occurring during the induction and prevention of autoimmune-mediated demyelination detected by FT-IR imaging

Publisher: Elsevier BV

Date: 2010

DOI: 10.1016/J.NEUROIMAGE.2009.09.053

Abstract: Multiple sclerosis (MS) is an inflammatory, demyelinating and neurodegenerative disease of the central nervous system (CNS). Despite progress in understanding immunogenetic aspects of this disease, the mechanisms involved in lesion formation are unknown. To gain new insights into the neuropathology of MS, we used an innovative integration of Fourier transform infrared (FT-IR) microspectroscopy, bioinformatics, and a synchrotron light source to analyze macromolecular changes in the CNS during the course and prevention of experimental autoimmune encephalomyelitis (EAE), an animal model for MS. We report that subtle chemical and structural changes not observed by conventional histology were detected before the onset of clinical signs of EAE. Moreover, trained artificial neural networks (ANNs) could discriminate, with excellent sensitivity and specificity, pathology from surrounding tissues and the early stage of the disease progression. Notably, we show that this novel measurement platform can detect characteristic differences in biochemical composition of lesion pathology in animals partially protected against EAE by vaccination with Nogo-A, an inhibitor of neural outgrowth, demonstrating the potential for automated screening and evaluation of new therapeutic agents.

A new approach to studying the effects of ionising radiation on single cells using FTIR synchrotron microspectroscopy

Publisher: Elsevier BV

Date: 12-2013

DOI: 10.1016/J.RADPHYSCHEM.2013.03.037

Comparison of FTIR transmission and transfection substrates for canine liver cancer detection

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4AN01901F

Abstract: FTIR spectroscopy is a widely used technique that provides insights into disease processes at the molecular level.

Interaction of quinoline antimalarial drugs with ferriprotoporphyrin IX, a solid state spectroscopy study

Publisher: Elsevier BV

Date: 12-2011

DOI: 10.1016/J.JINORGBIO.2011.08.005

Abstract: To investigate the nature of binding of quinoline antimalarial drugs to heme and to extract experimental evidence for this binding, the interaction of ferriprotoporphyrin IX (FP) with chloroquine and quinacrine (both of which have a similar side chain) and quinoline methanol antimalarials quinine and mefloquine has been studied using IR and NIR-Raman spectroscopy in the solid state. Attenuated total reflectance infrared spectroscopic data clearly show that heme in chloroquine-FP complex is not μ-oxo dimeric indicating that the hypothesis that chloroquine binds to FP μ-oxo dimer with a stoichiometry of 1 chloroquine:2 μ-oxo dimers is not valid in the solid state. Moreover, the first vibrational spectroscopy evidence is presented for the formation of hydrogen bonding between a propionate group of heme and the tertiary amino nitrogen of chloroquine and quinacrine. Raman spectroscopy data does not provide any evidence to support the formation of a similar salt bridge in the complexes of FP with quinine and mefloquine however, it suggests that the interaction of these drugs with FP happens through coordination of the Fe(III) center of the porphyrin to the 9-hydroxy group of the drug.

Efficient long-range conduction in cable bacteria through nickel protein wires

Publisher: Cold Spring Harbor Laboratory

Date: 23-10-2020

DOI: 10.1101/2020.10.23.351973

Abstract: Filamentous cable bacteria display unrivalled long-range electron transport, generating electrical currents over centimeter distances through a highly ordered network of fibers embedded in their cell envelope. The conductivity of these periplasmic wires is exceptionally high for a biological material, but their chemical structure and underlying electron transport mechanism remain unresolved. Here, we combine high-resolution microscopy, spectroscopy, and chemical imaging on in idual cable bacterium filaments to demonstrate that the periplasmic wires consist of a conductive protein core surrounded by an insulating shell layer. The core proteins contain a sulfur-ligated nickel cofactor, and conductivity decreases when nickel is oxidized or selectively removed. The involvement of nickel as the active metal in biological conduction is remarkable, and suggests a hitherto unknown form of electron transport that enables efficient conduction in centimeter-long protein structures.

The use of Resonant X-ray Emission Spectroscopy (RXES) for the electronic analysis of metal complexes and their interactions with biomolecules

Publisher: Elsevier BV

Date: 09-2015

DOI: 10.1016/J.DDTEC.2015.07.001

Abstract: This review presents a new application of Resonant X-ray Emission Spectroscopy (RXES) to study the mechanism of action of metal containing anticancer derivatives and in particular platinum in situ and in vivo. The technique is an ex le of a photon-in photon-out X-ray spectroscopic approach, which enables chemical speciation of drugs to be determined and therefore to derive action mechanisms, and to determine drug binding rates under physiological conditions and therapeutic concentrations. This is made feasible due to the atomic specificity and high penetration depth of RXES. The review presents ex les of the three main types of information that can be obtained by RXES and establishes an experimental protocol to perfect the measurements within cells.

Synchrotron-Infrared Microspectroscopy of Live Leishmania major Infected Macrophages and Isolated Promastigotes and Amastigotes

Publisher: American Chemical Society (ACS)

Date: 14-02-2023

DOI: 10.1021/ACS.ANALCHEM.2C04004

Spectropathology for the next generation: Quo vadis?

Publisher: Royal Society of Chemistry (RSC)

Date: 2015

DOI: 10.1039/C4AN02036G

Abstract: Vibrational spectroscopy for biomedical applications has shown great promise although its translation into clinical practice has, as yet, been relatively slow. This Editorial assesses the challenges facing the field and the potential way forward.

Haemozoin (β‐haematin) biomineralization occurs by self‐assembly near the lipid/water interface

Publisher: Wiley

Date: 09-2006

DOI: 10.1016/J.FEBSLET.2006.08.043

Abstract: Several blood-feeding organisms, including the malaria parasite detoxify haem released from host haemoglobin by conversion to the insoluble crystalline ferriprotoporphyrin IX dimer known as haemozoin. To date the mechanism of haemozoin formation has remained unknown, although lipids or proteins have been suggested to catalyse its formation. We have found that beta-haematin (synthetic haemozoin) forms rapidly under physiologically realistic conditions near octanol/water, pentanol/water and lipid/water interfaces. Molecular dynamics simulations show that a precursor of the haemozoin dimer forms spontaneously in the absence of the competing hydrogen bonds of water, demonstrating that this substance probably self-assembles near a lipid/water interface in vivo.

An improved model for malaria pigment and β‐hematin: Fe(OEP)picrate

Publisher: Wiley

Date: 16-08-2017

DOI: 10.1002/JRS.5176

Multimodal vibrational imaging of cells

Publisher: Elsevier BV

Date: 07-2017

DOI: 10.1016/J.VIBSPEC.2016.07.017

Monitoring UVR induced damage in single cells and isolated nuclei using SR-FTIR microspectroscopy and 3D confocal Raman imaging

Publisher: Royal Society of Chemistry (RSC)

Date: 2014

DOI: 10.1039/C4AN00838C

Abstract: Melanocytes exposed to artificial sunlight and analysed with FTIR and Raman spectroscopy show changes in DNA bands and evidence of lipid accumulation.

Resonance Raman spectroscopy of red blood cells using near-infrared laser excitation

Publisher: Springer Science and Business Media LLC

Date: 07-12-2006

DOI: 10.1007/S00216-006-0881-8

Abstract: Resonance Raman spectra of oxygenated and deoxygenated functional erythrocytes recorded using 785 nm laser excitation are presented. The high-quality spectra show a mixture of enhanced A(1g), A(2g), B(1g), B(2g), E(u) and vinyl modes. The high sensitivity of the Raman system enabled spectra from four oxygenation and deoxygenation cycles to be recorded with only 18 mW of power at the s le over a 60-minute period. This low power prevented photo-/thermal degradation and negated protein denaturation leading to heme aggregation. The large database consisting of 210 spectra from the four cycles was analyzed with principal components analysis (PCA). The PC1 loadings plot provided exquisite detail on bands associated with the oxygenated and deoxygenated states. The enhancement of a band at 567 cm(-1), observed in the spectra of oxygenated cells and the corresponding PC1 loadings plot, was assigned to the Fe-O(2) stretching mode, while a band appearing at 419 cm(-1) was assigned to the Fe-O-O bending mode based on previous studies. For deoxygenated cells, the enhancement of B(1g) modes at 785 nm excitation is consistent with vibronic coupling between band III and the Soret transition. In the case of oxygenated cells, the enhancement of iron-axial out-of-plane modes and non-totally symmetric modes is consistent with enhancement into the y,z-polarized transition a(iu)(pi)-->d(xz)+O(2)(pi(g)) centered at 785 nm. The enhancement of non-totally symmetric B(1g) modes in oxygenated cells suggests vibronic coupling between band IV and the Soret band. This study provides new insights into the vibrational dynamics, electronic structure and resonant enhancement of heme moieties within functional erythrocytes at near-IR excitation wavelengths.

FPA Imaging and Spectroscopy for Monitoring Chemical Changes in Tissue

Publisher: Wiley

Date: 22-11-2005

DOI: 10.1002/9780470988541.CH10

Evidence of altered biochemical composition in the hearts of adult intrauterine growth-restricted rats

Publisher: Springer Science and Business Media LLC

Date: 29-05-2013

DOI: 10.1007/S00394-012-0381-X

Recent Advances in Macro ATR-FTIR Microspectroscopic Technique for High Resolution Surface Characterisation at Australian Synchrotron IR Beamline

Publisher: OSA

Date: 2018

DOI: 10.1364/MICS.2018.MT3C.5

Vibrational spectroscopy combined with transcriptomic analysis for investigation of bacterial responses towards acid stress

Publisher: Springer Science and Business Media LLC

Date: 29-10-2017

DOI: 10.1007/S00253-017-8561-5

Abstract: The ability of bacteria to tolerate acid stress plays an important role in their growth and survival. In particular, aciduric bacteria have several survival systems that prevent cell damage from acid stress. In this study, the effect of the bacterial stress induced by pre-adaptation at different pH values on the cellular macromolecules of Lactobacillus plantarum was investigated using Raman spectroscopy and Fourier transform infrared spectroscopy. The expression of key genes was also quantified to provide understanding of the transcriptional response of the cells to lethal acid stress conditions. Principal component analysis of the spectra exhibited marked differences in the spectral regions associated with carbohydrates, lipids, proteins, and nucleic acids for all acid-stressed cells compared to those of untreated control cells. The changes in spectroscopic and transcriptomic profiles that were observed revealed alterations in bacterial cell wall composition after acid treatment. The results suggest the existence of a complex bacterial stress response in which modifications of cellular compounds from pre-adaption at low pH are involved. This study demonstrates the potential application of vibrational spectroscopy techniques to discriminate between intact and injured bacterial cells as well as to study their stress responses after exposure to acid environments during food processing.

Infrared spectroscopy coupled to cloud-based data management as a tool to diagnose malaria: a pilot study in a malaria-endemic country

Publisher: Springer Science and Business Media LLC

Date: 16-10-2019

DOI: 10.1186/S12936-019-2945-1

Abstract: Widespread elimination of malaria requires an ultra-sensitive detection method that can detect low parasitaemia levels seen in asymptomatic carriers who act as reservoirs for further transmission of the disease, but is inexpensive and easy to deploy in the field in low income settings. It was hypothesized that a new method of malaria detection based on infrared spectroscopy, shown in the laboratory to have similar sensitivity to PCR based detection, could prove effective in detecting malaria in a field setting using cheap portable units with data management systems allowing them to be used by users inexpert in spectroscopy. This study was designed to determine whether the methodology developed in the laboratory could be translated to the field to diagnose the presence of Plasmodium in the blood of patients presenting at hospital with symptoms of malaria, as a precursor to trials testing the sensitivity of to detect asymptomatic carriers. The field study tested 318 patients presenting with suspected malaria at four regional clinics in Thailand. Two portable infrared spectrometers were employed, operated from a laptop computer or a mobile telephone with in-built software that guided the user through the simple measurement steps. Diagnostic modelling and validation testing using linear and machine learning approaches was performed against the gold standard qPCR. S le spectra from 318 patients were used for building calibration models (112 positive and 110 negative s les according to PCR testing) and independent validation testing (39 positive and 57 negatives s les by PCR). The machine learning classification (support vector machines SVM) performed with 92% sensitivity (3 false negatives) and 97% specificity (2 false positives). The Area Under the Receiver Operation Curve (AUROC) for the SVM classification was 0.98. These results may be better than as stated as one of the spectroscopy false positives was infected by a Plasmodium species other than Plasmodium falciparum or Plasmodium vivax , not detected by the PCR primers employed. In conclusion, it was demonstrated that ATR-FTIR spectroscopy could be used as an efficient and reliable malaria diagnostic tool and has the potential to be developed for use at point of care under tropical field conditions with spectra able to be analysed via a Cloud-based system, and the diagnostic results returned to the user’s mobile telephone or computer. The combination of accessibility to mass screening, high sensitivity and selectivity, low logistics requirements and portability, makes this new approach a potentially outstanding tool in the context of malaria elimination programmes. The next step in the experimental programme now underway is to reduce the s le requirements to fingerprick volumes.

Monash University

Location: Australia

View Organisation

Discovery Projects - Grant ID: DP0878464

Start Date: 2008

End Date: 12-2012

Amount: $625,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP150100465

Start Date: 12-2015

End Date: 08-2018

Amount: $213,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0556559

Start Date: 2005

End Date: 01-2008

Amount: $300,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP0664012

Start Date: 01-2006

End Date: 12-2008

Amount: $290,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP140102504

Start Date: 2014

End Date: 08-2017

Amount: $410,000.00

Funder: Australian Research Council

ARC Future Fellowships - Grant ID: FT120100926

Start Date: 12-2012

End Date: 12-2017

Amount: $797,823.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP120100431

Start Date: 2012

End Date: 12-2015

Amount: $300,000.00

Funder: Australian Research Council

Discovery Projects - Grant ID: DP180103484

Start Date: 2018

End Date: 12-2023

Amount: $649,632.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE100100215

Start Date: 2010

End Date: 12-2010

Amount: $350,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE120100166

Start Date: 06-2012

End Date: 12-2013

Amount: $240,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP0347711

Start Date: 07-2003

End Date: 12-2005

Amount: $193,035.00

Funder: Australian Research Council

Industrial Transformation Training Centres - Grant ID: IC190100034

Start Date: 12-2020

End Date: 12-2025

Amount: $3,574,272.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0883036

Start Date: 01-2008

End Date: 10-2008

Amount: $400,000.00

Funder: Australian Research Council

Linkage Projects - Grant ID: LP160100731

Start Date: 12-2016

End Date: 12-2019

Amount: $388,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE220100140

Start Date: 10-2022

End Date: 10-2023

Amount: $699,691.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0560716

Start Date: 05-2005

End Date: 12-2006

Amount: $864,610.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE0668403

Start Date: 2006

End Date: 12-2007

Amount: $570,000.00

Funder: Australian Research Council

Linkage Infrastructure, Equipment And Facilities - Grant ID: LE160100185

Start Date: 03-2016

End Date: 12-2017

Amount: $400,000.00

Funder: Australian Research Council