ORCID Profile
0000-0002-6779-4736
Current Organisation
Institute of Bioorganic Chemistry, Polish Academy of Sciences
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: The Royal Society
Date: 06-04-2017
Abstract: The balance of oxidants and antioxidants within the cell is crucial for maintaining health, and regulating physiological processes such as signalling. Consequently, imbalances between oxidants and antioxidants are now understood to lead to oxidative stress, a physiological feature that underlies many diseases. These processes have spurred the field of chemical biology to develop a plethora of sensors, both small-molecule and fluorescent protein-based, for the detection of specific oxidizing species and general redox balances within cells. The mitochondrion, in particular, is the site of many vital redox reactions. There is therefore a need to target redox sensors to this particular organelle. It has been well established that targeting mitochondria can be achieved by the use of a lipophilic cation-targeting group, or by utilizing natural peptidic mitochondrial localization sequences. Here, we review how these two approaches have been used by a number of researchers to develop mitochondrially localized fluorescent redox sensors that are already proving useful in providing insights into the roles of reactive oxygen species in the mitochondria.
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.FREERADBIOMED.2018.03.008
Abstract: Here we describe new fluorescent probes based on fluorescein and rhodamine that provide reversible, real-time insight into cellular redox status. The new probes incorporate bio-imaging relevant fluorophores derived from fluorescein and rhodamine linked with stable nitroxide radicals such that they cannot be cleaved, either spontaneously or enzymatically by cellular processes. Overall fluorescence emission is determined by reversible reduction and oxidation, hence the steady state emission intensity reflects the balance between redox potentials of critical redox couples within the cell. The permanent positive charge on the rhodamine-based probes leads to their rapid localisation within mitochondria in cells. Reduction and oxidation also leads to marked changes in the fluorophore lifetime, enabling monitoring by fluorescence lifetime imaging microscopy. Finally, we demonstrate that administration of a methyl ester version of the rhodamine-based probe can be used at concentrations as low as 5 nM to generate a readily detected response to redox stress within cells as analysed by flow cytometry.
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8CC07092J
Abstract: A novel, reversible redox-active MRI probe, GdNR1, has been developed based on the biologically-inspired nicotinimidium redox switch.
Publisher: Wiley
Date: 13-05-2013
Abstract: A bicyclic ligand platform for iron(II), which allows total control over the complex's magnetic properties in aqueous solution simply by varying one of the six coordination sites of the bispidine ligand, is reported. To achieve this, an efficient synthetic route to an N5 bispidine framework (ligand L4) that features an unsubstituted N-7 site is established. Then, by choosing appropriate N-7-coordinating substituents, the spin state of choice can be imposed on the corresponding ferrous complexes under environmentally relevant conditions in water and near-room temperature. Importantly, the first low-spin and diamagnetic iron(II) chelates in the bispidine series, both in the solid state and in aqueous solution, are reported. The eradication of head-on steric clashes between pendent coordinating arms is at the origin of this success. A new pair of constitutionally similar ferrous coordination compounds of a multidentate ligand system is obtained, which exhibits a distinctly binary (off-on) magnetic relationship. The new synthetic intermediate L4 may be substituted in just one step by any desired pendent arm, thus allowing access to complexes with finely tuned magnetic properties.
Publisher: Springer Science and Business Media LLC
Date: 17-08-2023
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZBPYX
Publisher: eLife Sciences Publications, Ltd
Date: 2019
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ95KZ
Publisher: The Royal Society
Date: 07-2018
Abstract: Silver-containing nanomaterials are of interest for their antibiotic properties, for a wide range of applications from medicine to consumer products. However, much remains to be learnt about the degradation of such materials and their effects on human health. While most analyses involve measurement of total silver levels, it is important also to be able to measure concentrations of active free Ag(I) ions. We report here the preparation of a coumarin-based probe, thiocoumarin silver sensor 1 ( TcAg1 ), that responds reversibly to the addition of silver ions through the appearance of a new fluorescence emission peak at 565 nm. Importantly, this peak is not observed in the presence of Hg(II), a common interferent in Ag(I) sensing. To establish the utility of this sensor, we prepared silver-doped phosphate glasses with demonstrated bactericidal properties, and observed the Ag(I) release from these glasses in solutions of different ionic strength. TcAg1 is therefore a useful tool for the study of the environmental and medical effects of silver-containing materials.
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/CH19398
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ95N2
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ95L0
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6RA04643F
Abstract: A cobalt tris(2-pyridylmethyl)amine complex cycles between stable paramagnetic Co( ii ) and diamagnetic Co( iii ) forms with corresponding changes in the MRI contrast.
Publisher: Wiley
Date: 02-12-2016
Abstract: The redox chemistry of the cell is key to its function and health, and the development of chemical tools to study redox biology is important. While fluxes in oxidative state are essential for healthy cell function, a chronically elevated oxidative capacity is linked to disease. It is therefore essential that probes of biological redox states distinguish between these two conditions by the reversible sensing of changes over time. In this review, we discuss the current progress towards such probes, and identify key directions for future research in this nascent field of vital biological interest.
Publisher: Springer Science and Business Media LLC
Date: 19-03-2023
Publisher: Elsevier BV
Date: 03-2019
Publisher: Mary Ann Liebert Inc
Date: 05-2016
Abstract: Recent research has identified key roles for reactive oxygen species (ROS)/reactive nitrogen species (RNS) in redox signaling, but much remains to be uncovered. Molecular imaging tools to study these processes must not only be selective to enable identification of the ROS/RNS involved but also reversible to distinguish signaling processes from oxidative stress. Fluorescent sensors offer the potential to image such processes with high spatial and temporal resolution. A broad array of strategies has been developed that enable the selective sensing of ROS/RNS. More recently, attention has turned to the design of reversible small-molecule sensors of global redox state, with a further set of probes capable of reversible sensing of in idual ROS/RNS. In this study, we discuss the key challenges in achieving simultaneous detection of reversible oxidative bursts with unambiguous determination of a particular ROS/RNS. We have highlighted key design features of small-molecule probes that show promise in enabling the study of redox signaling, identifying essential parameters that must be assessed for any new probe. Antioxid. Redox Signal. 24, 713-730.
Publisher: The Company of Biologists
Date: 20-07-2021
DOI: 10.1242/JCS.258322
Abstract: The lipid content of mammalian cells varies greatly between cell type. Current methods for analysing lipid components of cells are technically challenging and destructive. Here, we report a facile, inexpensive method to identify lipid content – intracellular flow cytometric lipid analysis (IFCLA). Distinct lipid classes can be distinguished by Nile Blue fluorescence, Nile Red fluorescence or violet autofluorescence. Nile Blue is fluorescent in the presence of unsaturated fatty acids with a carbon chain length greater than 16. Cis-configured fatty acids induce greater Nile Blue fluorescence than their trans-configured counterparts. In contrast, Nile Red exhibits greatest fluorescence in the presence of cholesterol, cholesteryl esters, some triglycerides and phospholipids. Multiparametric spanning-tree progression analysis for density-normalized events (SPADE) analysis of hepatic cellular lipid distribution, including vitamin A autofluorescence, is presented. This flow cytometric system allows for the rapid, inexpensive and non-destructive identification of lipid content, and highlights the differences in lipid biology between cell types by imaging and flow cytometry. This article has an associated First Person interview with the first author of the paper.
Publisher: Oxford University Press (OUP)
Date: 2016
DOI: 10.1039/C6MT00083E
Abstract: Ratiometric probe for Cu( i ) reveals influence of cisplatin on mitochondrial copper homeostasis.
Publisher: Wiley
Date: 22-06-2017
Abstract: The use of fluorescent markers and probes greatly enhances biological investigations but relies on the provision of an array of fluorophores with erse properties. Herein we report a novel carborane-containing coumarin, 5, which is sufficiently lipophilic to localise in cellular lipid droplets. In non-polar solvents which show comparable polarities to those of a lipid environment, compound 5 exhibits a fluorescence quantum yield two orders of magnitude greater than found in aqueous solvents, adding a further degree of selectivity to lipid droplet imaging. Compound 5 can stain lipid droplets in ex vivo adipocytes as well as in cultured cells, and can be utilised in flow cytometry as well as confocal microscopy.
Publisher: MDPI AG
Date: 11-04-2020
DOI: 10.3390/MOLECULES25081761
Abstract: Amide bonds are among the most interesting and abundant molecules of life and products of the chemical pharmaceutical industry. In this work, we describe a method of the direct synthesis of amides from carboxylic acids and amines under solvent-free conditions using minute quantities of ceric ammonium nitrate (CAN) as a catalyst. The reactions are carried out in an open microwave reactor and allow the corresponding amides to be obtained in a fast and effective manner when compared to other procedures of the direct synthesis of amides from acids and amines reported so far in the literature. The amide product isolation procedure is simple, environmentally friendly, and is performed with no need for chromatographic purification of secondary amides due to high yields. In this report, primary amines were used in most ex les. However, the developed procedure seems to be applicable for secondary amines as well. The methodology produces a limited amount of wastes, and a catalyst can be easily separated. This highly efficient, robust, rapid, solvent-free, and additional reagent-free method provides a major advancement in the development of an ideal green protocol for amide bond formation.
Publisher: Oxford University Press (OUP)
Date: 2018
DOI: 10.1039/C7MT00297A
Abstract: A coumarin–calcein conjugate responds to changes in subcellular iron levels and enables study of iron chelation agents.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7CC00619E
Abstract: A cobalt( ii ) complex can distinguish between anions by observing the paramagnetic 1 H NMR shift.
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C7CS00528H
Abstract: This review identifies and discusses fluorescent sensors that are capable of simultaneously reporting on the presence of two analytes for biological application.
Publisher: Elsevier BV
Date: 05-2011
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ95JY
Publisher: Wiley
Date: 16-10-2017
Publisher: American Chemical Society (ACS)
Date: 28-05-2019
DOI: 10.1021/ACS.INORGCHEM.9B00340
Abstract: We present evidence of a spin-state change that accompanies desilylation reactions performed on two related Fe(II) iminopyridine coordination complexes. To probe these systems, we performed titrations with CsF in solution and analyzed the speciation with in situ magnetometry, electrochemistry, and mass spectrometry techniques. We find that pendant tert-butyldimethylsilyl groups are readily cleaved under these conditions, and the resulting desilylated complexes exhibit overall decreased solution magnetic susceptibility values. Density functional theory and ab initio computations probe the impact of substituent identity (prior to- and post-desilylation) on the metal-ligand σ-donor and π-acceptor bonding properties. We attribute the observed spin-state changes to the decrease in entropy associated with the conformational freedom of the silylated high-spin complex, resulting in a more favored low-spin state upon desilylation.
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ8XBG
Publisher: Elsevier BV
Date: 02-2018
Publisher: Springer New York
Date: 2017
Publisher: No publisher found
Date: 2013
DOI: 10.5517/CCZ95M1
Publisher: Wiley
Date: 26-11-2014
Abstract: This Minireview aims to shed light on the emergent field of inducing a change in the magnetic properties of a solution-phase s le by exposing it to a chemical analyte. A considerable body of knowledge exists on materials that alter their magnetic characteristics after a change in the surrounding physical conditions and a number of cases even exist of solution-phase s les that do so under these same circumstances. However, ex les of dissolved molecules or particles that react in this fashion under constant conditions and in response to an analyte are limited. Although some cases in organic solvents are discussed, the emphasis of this Minireview is on water. Our aim is to provide the reader with guidelines for designing new magnetogenic probes for the detection of the desired chemical analyte.
Location: Poland
No related grants have been discovered for Jacek Kolanowski.