ORCID Profile
0000-0003-0709-2246
Current Organisation
Deakin University
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Publisher: Elsevier BV
Date: 12-2010
DOI: 10.1016/J.BIOMATERIALS.2010.08.068
Abstract: Two-photon microscopy powered by a femtosecond laser is a promising tool for luminescence imaging and localized microsurgery of cancers. However, the high energy required to destruct cells limits its medical applications. In this work, gold nanorods were conjugated with transferrin for efficient targeting, two-photon luminescence imaging and enhanced microsurgery of cancer cells. Due to the large two-photon excitation cross section of gold nanorods, gold nanorods are a hundred times more efficient than Fluorescein isothiocyanate (FITC), a common molecular dye, in three-dimensional imaging of cancer cells. The enhanced light absorption and energy conversion by gold nanorods enable treatment of cells with energy fluences two orders of magnitude below that in the absence of gold nanorods. By manipulating the energy fluence, apoptosis of cancer cells has been achieved. At a same power density, the energy fluence for apoptosis induction is less than 20% of that for necrosis. Gold nanorods-enhanced luminescence imaging coupled with apoptosis induction of cancer cells provides a medically safe femtosecond laser-based imaging and microsurgery system for cancer diagnosis and treatment.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7CP03004E
Abstract: Gold nanorod based nanosensors can be used to recognize chiral zwitterionic interactions by an on/off plasmonic CD response.
Publisher: Institute of Electrical and Electronics Engineers (IEEE)
Date: 07-2010
Publisher: Elsevier BV
Date: 12-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2012
DOI: 10.1039/C2SM25073J
Publisher: Elsevier BV
Date: 02-2018
Publisher: Elsevier BV
Date: 06-2017
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7CC03122J
Abstract: Through the combination of central naphthalene diimide and terminal rhodanine or 1,3-indanedione functionalities, two new non-fullerene electron acceptors, coded as N3 and N4 , were designed, synthesized and characterized.
Publisher: Wiley
Date: 18-12-2021
Abstract: Electrocatalysts used for oxygen reduction and oxygen evolution reactions are critical materials in many renewable-energy devices, such as rechargeable metal-air batteries, regenerative fuel cells, and water-splitting systems. Compared with conventional electrodes made from catalyst powders, oxygen electrodes with a freestanding architecture are highly desirable because of their binder-free fabrication and effective elimination of catalyst agglomeration. Among all freestanding electrode structures that have been investigated so far, fibrous materials exhibit many unique advantages, such as a wide range of available fibers, low material and material-processing costs, large specific surface area, highly porous structure, and simplicity of fiber functionalization. Recent advances in the use of fibrous structures for freestanding electrocatalytic oxygen electrodes are summarized, including electrospun nanofibers, bacterial cellulose, cellulose fibrous structures, carbon clothes apers, metal nanowires, and metal meshes. After detailed discussion of common techniques for oxygen electrode evaluation, freestanding electrode fabrication, and their electrocatalytic performance, current challenges and future prospects are also presented for future development.
Publisher: Elsevier BV
Date: 08-2019
Publisher: AIP Publishing
Date: 08-02-2010
DOI: 10.1063/1.3302461
Abstract: We report on the use of a radially polarized beam for photothermal therapy of cancer cells labeled with gold nanorods. Due to a three-dimensionally distributed electromagnetic field in the focal volume, the radially polarized beam is proven to be a highly efficient laser mode to excite gold nanorods randomly oriented in cancer cells. As a result, the energy fluence for effective cancer cell damage is reduced to one fifth of that required for a linearly polarized beam, which is only 9.3% of the medical safety level.
Publisher: Wiley
Date: 13-03-2019
Abstract: Antimicrobial peptides (AMPs) promise a fundamental solution to the devastating threat of drug-resistant bacteria. However, drawbacks of AMPs (e.g., poor cell membrane penetration efficiency) seriously block their clinical use. In this work, rational design of a hybrid complex of melittin (as a representative AMP) and graphene or graphene oxide (Gra or GO) nanosheets for enhanced antibacterial ability is achieved, via combining in-silico prediction and in-tube test. In comparison to pristine melittin, the specifically designed AMP-Gra (/GO) complex exhibits remarkable efficiency in transmembrane perforation with an over tenfold decrease in the threshold working concentration of peptide moreover, it has an up to 20-fold enhancement in antibacterial activity against both Gram-negative and Gram-positive bacteria. Such improvement is ascribed to the synergetic insertion of nanosheets and melittin due to similarity in antibacterial mechanism between them and is further regulated by the structural factors of the complex, including the intersheet spacing and surface functionalization of the Gra/GO sheets, etc. These results provide practical guidelines to engineer AMPs with nanotechnology for improved antimicrobial performances, especially based on targeted functionalization of the Gra/GO nanosheets.
Publisher: American Chemical Society (ACS)
Date: 21-03-2013
DOI: 10.1021/JP311727T
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C5RA20201A
Abstract: E-beam exposure unzips beta-sheets in crystalline domains of silk fibroin and makes it water-soluble, enabling its usage as an aqueous-based electron beam lithography resist.
Publisher: Elsevier BV
Date: 05-2015
DOI: 10.1016/J.BBAMEM.2015.02.018
Abstract: The response of cell membranes to the local physical environment significantly determines many biological processes and the practical applications of biomaterials. A better understanding of the dynamic assembly and environmental response of lipid membranes can help understand these processes and design novel nanomaterials for biomedical applications. The present work demonstrates the directed assembly of lipid monolayers, in both liquid and gel phases, on the surface of a monolayered reduced graphene oxide (rGO). The results from atomic force microscopy indicate that the hydrophobic aromatic plane and the defect holes due to reduction of GO sheets, along with the phase state and planar surface pressure of lipids, corporately determine the morphology and lateral structure of the assembled lipid monolayers. The DOPC molecules, in liquid phase, probably spread over the rGO surface with their tails associating closely with the hydrophobic aromatic plane, and accumulate to form circles of high area surrounding the defect holes on rGO sheets. However, the DPPC molecules, in gel phase, prefer to form a layer of continuous membrane covering the whole rGO sheet including defect holes. The strong association between rGO sheets and lipid tails further influences the melting behavior of lipids. This work reveals a dramatic effect of the local structure and surface property of rGO sheets on the substrate-directed assembly and subsequent phase behavior of the supported lipid membranes.
Publisher: Elsevier BV
Date: 12-2013
DOI: 10.1016/J.BIOMATERIALS.2013.08.066
Abstract: Nanosized graphene and graphene oxide (GO) are photoluminescent due to the presence of bandgaps and edges/defects. The excellent photostability of these nanomaterials makes them superior to molecular dyes for biological imaging. They can also produce intensive heat under laser irradiation, enabling them to serve as photothermal agents for cancer treatment. In this work, recent studies on the photoluminescence of these materials, their applications for biological imaging and photothermal cancer therapy are reviewed. Properties of laser, particularly the temporal property (continuous wave or pulsed), affect its interaction with materials. Therefore, the photoluminescence and photothermal effects, as well as their applications under both single (one)-photon (continuous wave laser) and two-photon (pulsed laser) excitation were summarized and analyzed. Synergistic therapy which combines chemotherapy and photothermal therapy using these materials is also reviewed. Finally, critical issues and challenges for further research and in medical applications of these materials are analyzed.
Publisher: American Chemical Society (ACS)
Date: 29-12-2021
DOI: 10.1021/ACS.LANGMUIR.1C01312
Abstract: Functionalization of silk fibroin hydrogel with antimicrobial activity is essential for promoting the applications of this excellent biomaterial. In this work, a simple approach based on electrostatic interaction is adopted to produce antimicrobial silk hydrogel containing an antimicrobial peptide (AMP), polymyxin B, an important last-line antibiotic to treat multidrug-resistant bacterial superbugs. The polycationic property of this peptide and the negative charge of silk fibroin lead to strong interactions between them, as demonstrated by changes in nanofibril structure, gelation kinetics, ζ-potential, fluorescence emission, and rheological properties of the gel. The hydrogels loaded with polymyxin B demonstrated antimicrobial activity against two Gram-negative bacterial strains. A combination of the results from the different characterizations suggests that the optimal molar ratio of polymyxin B to silk fibroin is 1:2.5. As most AMPs are cationic, this electrostatic approach is suitable for the straightforward functionalization of inert silk hydrogel with other AMPs.
Publisher: Elsevier BV
Date: 05-2023
Publisher: Royal Society of Chemistry (RSC)
Date: 2010
DOI: 10.1039/C0LC00090F
Abstract: A compact microfluidic device with 96 microchambers allocated within four circular units was designed and examined for cell distribution. In each unit, cells were distributed to the surrounding chambers radially from the center. The circular arrangement of the chambers makes the design simple and compact. A controllable and quantitative cell distribution is achievable in this device. This design is significant to the microfluidic applications where controllable distribution of cells in multipule microchambers is demanded.
Publisher: Elsevier BV
Date: 08-2009
Publisher: American Chemical Society (ACS)
Date: 23-03-2009
DOI: 10.1021/JP811215T
Abstract: The formation of most organogels requires the compatibility of both the gelator and solvent. It is very desirable if the rheological properties of a gel can be manipulated to achieve the desired performance. In this paper, a novel organogel was developed and its rheological properties and fiber network were engineered by controlling the thermal processing conditions. The gel was formed by the gelation of 12-hydroxystearic acid as a gelator in benzyl benzoate. It was observed that the degree of supercooling for gel formation has a significant effect on the rheological properties and fiber network structure. By increasing supercooling, the elasticity of the gel was enhanced, and the correlation length of the fibers was shortened, leading to the formation of denser fiber networks. The good biocompatibility of both the gelator and solvent makes this gel a promising vehicle for a variety of bioapplications such as controlled transdermal drug release and in vivo tissue repair.
Publisher: American Chemical Society (ACS)
Date: 14-06-2013
DOI: 10.1021/LA4015652
Abstract: Cellular uptake of materials plays a key role in their biomedical applications. In this work, based on the cell-mimic giant unilamellar vesicles (GUVs) and a novel type of microscale materials consisting of stimuli-responsive poly(N-isopropylacrylamide) microgel particles and the incorporated lipids, the influence of particle surface chemistry, including hydrophobic/hydrophilic property and lipid decorations, on the adsorption and consequent internalization of particles into GUVs was investigated. It is found that the decoration of particle surface with lipids facilitates the adsorption of particles on GUV membrane. After that, the hydrophobic property of particle surface further triggers the internalization of particles into GUVs. These results demonstrate the importance of surface properties of particles on their interactions with lipid membranes and are helpful to the understanding of cellular uptake mechanism.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0QM00515K
Abstract: A three-dimensional, non-planar, non-fullerene acceptor ( SFX1 ) ITO/PEDOT:PSS (38 nm)/active layer (∼75 nm)/Ca (20 nm)/Al (100 nm) PCE (PTB7 : SFX1 1 : 1.2) = 9.42%.
Publisher: Elsevier BV
Date: 2021
Publisher: Wiley
Date: 13-01-2012
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7TC03217J
Abstract: Conductive nanocellulose fibers were achieved by the wet-spinning of renewable cellulose nanofibrils (CNFs) and silver nanowires (AgNWs) from a single spinneret.
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.COLSURFB.2013.12.030
Abstract: Silk fibroin (SF) from Bombyx mori has many established excellent properties and has found various applications in the biomedical field. However, some abilities or capacities of SF still need improving to meet the need for using practically. Indeed, erse SF-based composite biomaterials have been developed. Here we report the feasibility of fabricating pantothenic acid (vitamin B5, VB5)-reinforcing SF nanofibrous matrices for biomedical applications through green electrospinning. Results demonstrated the successful loading of D-pantothenic acid hemicalcium salt (VB5-hs) into resulting composite nanofibers. The introduction of VB5-hs did not alter the smooth ribbon-like morphology and the silk I structure of SF, but significantly decreased the mean width of SF fibers. SF conformation transformed into β-sheet from random coil when composite nanofibrous matrices were exposed to 75% (v/v) ethanol vapor. Furthermore, nanofibers still remained good morphology after being soaked in water environment for five days. Interestingly, as-prepared composite nanofibrous matrices supported a higher level of cell viability, especially in a long culture period and significantly assisted skin cells to survive under oxidative stress compared with pure SF nanofibrous matrices. These findings provide a basis for further extending the application of SF in the biomedical field, especially in the personal skin-care field.
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8QM00067K
Abstract: A spiro[fluorene-9,9′-xanthene]-functionalized non-fullerene acceptor A1 [D : A1 = 1 : 1.2 P3HT(D) = 5.84%, PTB7(D) = 7.21%].
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.BBAMEM.2018.09.007
Abstract: Antimicrobial peptides (AMPs) provide a promising solution to the serious threat of multidrug-resistant bacteria or superbugs to public healthcare, due to their unique disruption to bacterial membrane such as perforation. Unfortunately, the underlying action mechanism of AMPs, especially the possible transition between the membrane binding and perforation states of peptides (i.e., the classical two-state model), is still largely unknown. Herein, by combining experimental techniques with pertinent membrane models and molecular dynamic (MD) simulations, new insights into the intermediate states of the AMP melittin-membrane interaction process are obtained. Specifically, it is demonstrated that, after the initial binding, the accumulated melittin on the bilayer triggers vigorous fluctuation of the membrane and even extracts some lipid molecules exclusively from the deformed outer leaflet of the bilayer. Such a distinctive mass removal manner and the resultant local asymmetry in lipid number between the two leaflets change the mechanical status of the membrane and in turn reduce the free energy barrier for the melittin insertion. Finally, the formation of the transmembrane pores is facilitated significantly. These findings provide new insights into the complicated antimicrobial mechanisms of AMPs.
Publisher: American Chemical Society (ACS)
Date: 14-09-2023
Publisher: MDPI AG
Date: 21-10-2022
DOI: 10.3390/GELS8100684
Abstract: In recent years, the treatment of textile waste has attracted more and more attention around the world. The reuse of textile waste can contribute to the reduction of carbon emissions and the sustainable development of the economy. Herein, we proposed a facile and cost-effective approach to fabricating aerogel by using textile waste fibers as the matrix and polyvinyl alcohol (PVA) and glutaraldehyde (GA) as crosslinking agents. After being modified with methyltrimethoxysilane (MTMS) via chemical vapor deposition, both the interior and exterior of the textile waste aerogels exhibit a hydrophobic property with a water contact angle of up to 136.9° ± 2.3°. A comprehensive investigation of the structure, thermal properties, mechanical properties and oil absorption capacity of this aerogel shows its potential for building insulation and oil spill cleanup. The textile waste fibers aerogels have low density and high porosity, good thermal stability and outstanding heat insulation properties (Kavg. = 0.049–0.061 W/m·K). With a maximum oil absorption value of 26.9 ± 0.6 g/g and rapid and effective oil/water mixture separation, the aerogel exhibits competitive commercial application value.
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.BBAMEM.2013.04.013
Abstract: Quartz crystal microbalance with dissipation (QCM-D) technique is one of the most effective methods to monitor the dynamic behaviors of a layer on a solid surface. Moreover, it has been reported recently that it is able to provide a fingerprint for the peptide-membrane interactions. In this work, QCM-D technique combined with computer simulations was employed to investigate the deposition and transformation of vesicles, as well as the subsequent membrane-melittin interactions on different substrates. A range of substrate surfaces, i.e. naked SiO2 without or with Au olyelectrolyte coating, were produced. The nature of the substrate determined whether the adsorbed vesicles were present as a high-quality supported bilayer or an assembled vesicle matrix, which consequently influenced the membrane-melittin interactions. It was indicated by the related computer simulations that the lipid packing state of the membrane was a key factor to determine the mechanism of membrane-peptide interactions. Furthermore, this work might be a good ex le of the application of QCM-D for the exploration of membrane-active peptides.
Publisher: MDPI AG
Date: 30-04-2014
DOI: 10.3390/MA7053481
Publisher: Oxford University Press (OUP)
Date: 10-09-2020
DOI: 10.1093/JAC/DKAA376
Abstract: MDR bacteria represent an urgent threat to human health globally. Polymyxins are a last-line therapy against life-threatening Gram-negative ‘superbugs’, including Acinetobacter baumannii. Polymyxins exert antimicrobial activity primarily via permeabilizing the bacterial outer membrane (OM) however, the mechanism of interaction between polymyxins and the OM remains unclear at the atomic level. We constructed a lipid A-based OM model of A. baumannii using quantitative membrane lipidomics data and employed all-atom molecular dynamics simulations with umbrella s ling techniques to elucidate the structure–interaction relationship and thermodynamics governing the penetration of polymyxins [B1 and E1 (i.e. colistin A) representing the two clinically used polymyxins] into the OM. Polymyxin B1 and colistin A bound to the A. baumannii OM by the initial electrostatic interactions between the Dab residues of polymyxins and the phosphates of lipid A, competitively displacing the cations from the headgroup region of the OM. Both polymyxin B1 and colistin A formed a unique folded conformation upon approaching the hydrophobic centre of the OM, consistent with previous experimental observations. Polymyxin penetration induced reorientation of the headgroups of the OM lipids near the penetration site and caused local membrane disorganization, thereby significantly increasing membrane permeability and promoting the subsequent penetration of polymyxin molecules into the OM and periplasmic space. The thermodynamics governing the penetration of polymyxins through the outer leaflet of the A. baumannii OM were examined and novel structure–interaction relationship information was obtained at the atomic and membrane level. Our findings will facilitate the discovery of novel polymyxins against MDR Gram-negative pathogens.
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6CC03730E
Abstract: A four-directional non-fullerene electron acceptor provided a PCE of 3.86% with an excellent high V oc of 1.18 V with the archetypal donor P3HT.
Publisher: Elsevier BV
Date: 08-2023
Publisher: American Chemical Society (ACS)
Date: 23-08-2001
DOI: 10.1021/ES0108335
Abstract: A novel but simple cloud-point extraction (CPE) process is developed to preconcentrate the trace of selected polycyclic aromatic hydrocarbons (PAHs) with the use of the readily biodegradable nonionic surfactant Tergitol 15-S-7 as extractant. The concentrations of PAHs, mixtures of naphthalene and phenanthrene as well as pyrene, in the spiked s les were determined with the new CPE process at ambient temperature (23 degrees C) followed by high performance liquid chromatography(HPLC) with fluorescence detection. More than 80% of phenanthrene and pyrene, respectively, and 96% of naphthalene initially present in the aqueous solutions with concentrations near or below their aqueous solubilities were recovered using this new CPE process. Importantly Tergitol 15-S-7 does not give any fluorometric signal to interfere with fluorescence detection of PAHs in the UV range. No special washing step is, thus, required to remove surfactant before HPLC analyses. Different experimental conditions were studied. The optimum conditions for the preconcentration and determination of these selected PAHs at ambient temperature have been established as the following: (1) 3 wt% surfactant (2) addition of 0.5 M Na2SO4 (3) 10 min for equilibration time and (4) 3000 rpm for centrifugal speed with duration of 10 min.
Publisher: American Chemical Society (ACS)
Date: 31-05-2011
DOI: 10.1021/LA200196K
Abstract: We present a new generic strategy to fabricate nanoparticles in the "cages" within the fibrous networks of supramolecular soft materials. As the cages can be acquired by a design-and-production manner, the size of nanoparticles synthesized within the cages can be tuned accordingly. To implement this idea, both selenium and silver were chosen for the detailed investigation. It follows that the sizes of selenium and silver nanoparticles can be controlled by tuning the pore size of the fiber networks in the material. When the concentration of the gelator is high enough, monodisperse nanoparticles can be prepared. More interestingly, the morphology of the nanoparticles can be altered: silver disks can be formed when the concentrations of both the gelator and silver nitrate are sufficiently low. As the fiber network serves as a physical barrier and semisolid support for the nanoparticles, the stability in the aqueous media and the ease of application of these nanoparticles can be substantially enhanced. This robust surfactant-free approach will not only allow the controlled fabrication of nanoparticles, but also can be applied to the fabrication of composite materials for robust applications.
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.CANLET.2008.09.024
Abstract: Gold nanoparticles were conjugated with transferrin molecules for targeting, imaging and therapy of breast cancer cells (Hs578T, ATCC). Results show that, the transferrin-transferrin receptor-mediated cellular uptake of gold nanoparticles is six times of that in the absence of this interaction. As a consequence, the laser power effective for photothermal therapy of the cancer cells was reduced to values of two orders of magnitude lower. To demonstrate the efficiency of the conjugated gold nanoparticles in selectively targeting cancer cells, the cellular uptake of the gold nanoparticles by noncancerous cells (3T3, ATCC) was also investigated. The cellular uptake by the normal cells is only one fourth of that by the cancerous cells indicating that the transferrin-transferrin receptor interaction plays an important role in controlling the cellular uptake of the gold nanoparticles.
Publisher: Wiley
Date: 18-12-2020
Publisher: American Chemical Society (ACS)
Date: 04-12-2017
Abstract: The development of advanced thermal transport materials is a global challenge. Two-dimensional nanomaterials have been demonstrated as promising candidates for thermal management applications. Here, we report a boron nitride (BN) nanosheet olymer composite film with excellent flexibility and toughness prepared by vacuum-assisted filtration. The mechanical performance of the composite film is highly flexible and robust. It is noteworthy that the film exhibits highly anisotropic properties, with superior in-plane thermal conductivity of around 200 W m
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5RA18513K
Abstract: Silver submicrospheres fabricated under an ambient condition can catalyze the reduction of 4-nitrophenol and improve significantly the Raman signal of crystal violet as surface-enhanced Raman scattering (SERS) substrate.
Publisher: American Chemical Society (ACS)
Date: 09-11-2016
DOI: 10.1021/ACS.LANGMUIR.6B03527
Abstract: Coassembly of molecules can produce materials with improved properties and functionalities. To this end, achieving a molecular level understanding of the interactions governing the coassembly is essential. In this work, two molecular gelators with significantly different structures and main intermolecular forces for assembly were coassembled. The elastic moduli of the hybrid gels are more than 1 order of magnitude higher than those of the gels formed by the in idual gelators, showing an obvious synergistic effect. The interactions between the gelators were investigated with confocal microscopy and both one-dimensional and two-dimensional nuclear magnetic resonance. It was found that the two gelators coassemble to form fibers due to the nonspecific van der Waals interactions between their alkyl chains and the specific interactions between their functional groups. Switching from one gelator-dominated fiber network to the other gelator-dominated fiber network was achieved at a critical molar ratio of the gelators. The two gelators serve as additives of each other to tune the nucleation and growth of the fiber networks. The observations of this work are significant to the development of materials with improved properties by coassembly of different molecules.
Publisher: Elsevier BV
Date: 08-2013
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C4RA09482D
Abstract: Both the physical and physiochemical properties of domestic and wild silkworm silk fibroin were studied, including surface energy and surface energy heterogeneity.
Publisher: IOP Publishing
Date: 22-11-2017
Publisher: Springer Science and Business Media LLC
Date: 24-01-2018
DOI: 10.1038/S41598-018-19721-3
Abstract: A correction to this article has been published and is linked from the HTML version of this paper. The error has been fixed in the paper.
Publisher: Elsevier BV
Date: 09-2023
Publisher: Elsevier BV
Date: 2020
Publisher: American Chemical Society (ACS)
Date: 30-05-2018
Abstract: The continuous evolution of tissue engineering scaffolds has been driven by the desire to recapitulate structural features and functions of the natural extracellular matrix (ECM). However, it is still an extreme challenge to create a three-dimensional (3D) scaffold with both aligned nanofibers and aligned interconnected macrochannels to mimic the ECM of anisotropic tissues. Here, we develop a facile strategy to create such a scaffold composed of oriented nanofibers and interconnected macrochannels in the same direction, with various natural polymers typically used for tissue regeneration. The orientation of nanofibers and interconnected macrochannels can be easily tuned by manipulating ice crystallization. The scaffold demonstrates both structural and functional features similar to the natural ECM of anisotropic tissues. Taking silk fibroin as an ex le, the scaffold with radially oriented nanofibers and interconnected macrochannels is more efficient for capturing cells and promoting the growth of both nonadherent embryonic dorsal root ganglion neurons (DRGs) and adherent human umbilical vein endothelial cells (HUVECs) compared to the widely used scaffold types. Interestingly, DRGs and neurites on the SF scaffold demonstrate a 3D growth mode similar to that of natural nerve tissues. Furthermore, the coaligned nanofibers and macrochannels of the scaffold can direct HUVECs to assemble into blood vessel-like structures and their collagen deposition in their arrangement direction. The strategy could inspire the design and development of multifunctional 3D scaffolds with desirable structural features for engineering different tissues.
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C3TA14999D
Publisher: Elsevier BV
Date: 09-2018
DOI: 10.1016/J.JCIS.2018.05.007
Abstract: Supramolecular assembly governs the formation and properties of many soft materials. Hence, it is significant to develop convenient approaches to control the assembly process. In this work, it is demonstrated that by using surfactants consisting of a sorbitan group (either ethoxylated or not) and an aliphatic chain, as additives, the fractal fiber network structure of a π gelator (with two alkyl chains) can be engineered. The two surfactants, which have the same hydrophobic tails but different hydrophilic heads, demonstrate different effects on the fiber network of the gelator. The surfactant with a large hydrophilic head (ethoxylated sorbitan) promotes fiber tip branching and that with a smaller hydrophilic head (non-ethoxylated sorbitan) enhances fiber side branching. Fractal analysis based on the Avrami model also demonstrates enhancement of fiber branching by the surfactants. Furthermore, the fluorescence emission of the gelator is enhanced by more than 30%. The observations have significant implications in engineering a class of supramolecular materials.
Publisher: Informa UK Limited
Date: 12-2009
Publisher: American Chemical Society (ACS)
Date: 02-11-2009
DOI: 10.1021/JP907963T
Abstract: The engineering of soft functional materials based on the construction of three-dimensional interconnecting self-organized nanofiber networks is reported. The system under investigation is an organogel formed by N-lauroyl-L-glutamic acid di-n-butylamide (GP-1) in propylene glycol. The engineering of soft functional materials is implemented by controlling primary nucleation kinetics of GP-1, which can be achieved by both reducing thermodynamic driving force and/or introducing a tiny amount of specific copolymers (i.e., poly(methyl methacrylate comethacrylic acid)). The primary nucleation rate of GP-1 is correlated to the number density of GP-1 spherulites, which determines the overall rheological properties of soft functional materials. The results show that the presence of a tiny amount of the polymer (0.01-0.06%) can effectively inhibit the nucleation of GP-1 spherulites, which leads to the formation of integrated fiber networks. It follows that with the additive approach, the viscoelasticity of the soft functional material is significantly enhanced (i.e., more than 1.5 times at 40 degrees C). A combination of the thermal and additive approach led to an improvement of 3.5 times in the viscosity of the gel.
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5RA09683A
Abstract: A self-assembled lipid membrane provides a smooth, hydrophilic and biocompatible surface coating film for materials.
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C4TB00070F
Abstract: A type of microgel composite consisting of pNIPAM microspheres and rGO nanoparticles shows both photo- and thermo-responsive drug release behaviors.
Publisher: No publisher found
Date: 2011
DOI: 10.1021/CG200501H
Publisher: Elsevier BV
Date: 02-2023
DOI: 10.1016/J.JCIS.2022.11.003
Abstract: This work aims to understand how pre-freezing treatments (-20 °C, -80 °C or -196 °C (liquid nitrogen)) affect the microstructure, mechanical properties and secondary structure of silk scaffolds prepared from lyophilization of silk hydrogels and silk solutions. It is found that in comparison with silk solutions, silk hydrogels at the same silk fibroin concentrations produce scaffolds with more nanofibrous structures when they are pre-frozen at the different temperatures. Although pre-freezing with liquid nitrogen can produce nanofibrous scaffolds from either a silk solution (low concentration of 2%) or silk hydrogel (produced from 2 to 6% silk fibroin solutions), aligned macro-channels can be produced only from silk hydrogels. In addition, scaffolds obtained from silk hydrogels are dominated by β-sheets due to the crystallization process for gel network formation, while scaffolds prepared from silk solutions are largely amorphous. The findings of this work are important to tune the microstructure and mechanical properties of silk scaffolds.
Publisher: Springer Science and Business Media LLC
Date: 02-2005
DOI: 10.1007/S10531-004-0429-1
Abstract: Biodegradation of poorly soluble polycyclic aromatic hydrocarbons (PAHs) has been a challenge in bioremediation. In recent years, surfactant-enhanced bioremediation of PAH contaminants has attracted great attention in research. In this study, biodegradation of phenanthrene as a model PAHs solubilized in saline micellar solutions of a biodegradable commercial alcohol ethoxylate nonionic surfactant was investigated. The critical micelle concentration (CMC) of the surfactant and its solubilization capacity for phenanthrene were examined in an artificial saline water medium, and a type of marine bacteria, Neptunomonas naphthovorans, was studied for the biodegradation of phenanthrene solubilized in the surfactant micellar solutions of the saline medium. It is found that the solubility of phenanthrene in the surfactant micellar solutions increased linearly with the surfactant concentrations, but, at a fixed phenanthrene concentration, the biodegradability of phenanthrene in the micellar solutions decreased with the increase of the surfactant concentrations. This was attributed to the reduced bioavailability of phenanthrene, due to its increased solubilization extent in the micellar phase and possibly lowered mass transfer rate from the micellar phase into the aqueous phase or into the bacterial cells. In addition, an inhibitory effect of the surfactant on the bacterial growth at high surfactant concentrations may also play a role. It is concluded that the surfactant largely enhanced the solubilization of phenanthrene in the saline water medium, but excess existence of the surfactant in the medium should be minimized or avoided for the biodegradation of phenanthrene by Neptunomonas naphthovorans.
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C4CP02874K
Abstract: Titanium dioxide quantum dots promote shape transformation of silver nanoparticles from nanoprisms to nanodecahedra upon ultraviolet light irradiation. The obtained silver nanodecahedra are reconverted to silver nanoprisms under sodium l .
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C2CC38779D
Abstract: Silk scaffolds having biomimetic hierarchical porous structures were achieved by carefully tuning liquid-liquid separation in regenerated silk fibroin solutions. Such scaffolds show greatly enhanced cellular responses.
Publisher: Elsevier BV
Date: 2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C4CP05715E
Abstract: Distinct kinetic feature of the molecular gelation in a confined or unconfined regime, and its relationship with the tailored fiber network structure and mechanical properties.
Publisher: MDPI AG
Date: 13-05-2019
DOI: 10.3390/NANO9050732
Abstract: Polariscopy is demonstrated using hyperspectral imaging with a focal plane array (FPA) detector in the infrared (IR) spectral region under illumination by thermal and synchrotron light sources. FPA Fourier-transform IR (FTIR) imaging microspectroscopy is useful for monitoring real time changes at specific absorption bands when combined with a high brightness synchrotron source. In this study, several types of s les with unique structural motifs were selected and used for assessing the capability of polariscopy under this FPA-FTIR imaging technique. It was shown that the time required for polariscopy at IR wavelengths can be substantially reduced by the FPA-FTIR imaging approach. By using natural and laser fabricated polymers with sub-wavelength features, alignment of absorbing molecular dipoles and higher order patterns (laser fabricated structures) were revealed. Spectral polariscopy at the absorption peaks can reveal the orientation of sub-wavelength patterns (even when they are not spatially resolved) or the orientation of the absorbing dipoles.
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C2CP43747C
Abstract: Understanding the role of kinetics in fiber network microstructure formation is of considerable importance in engineering gel materials to achieve their optimized performances/functionalities. In this work, we present a new approach for kinetic-structure analysis for fibrous gel materials. In this method, kinetic data is acquired using a rheology technique and is analyzed in terms of an extended Dickinson model in which the scaling behaviors of dynamic rheological properties in the gelation process are taken into account. It enables us to extract the structural parameter, i.e. the fractal dimension, of a fibrous gel from the dynamic rheological measurement of the gelation process, and to establish the kinetic-structure relationship suitable for both dilute and concentrated gelling systems. In comparison to the fractal analysis method reported in a previous study, our method is advantageous due to its general validity for a wide range of fractal structures of fibrous gels, from a highly compact network of the spherulitic domains to an open fibrous network structure. With such a kinetic-structure analysis, we can gain a quantitative understanding of the role of kinetic control in engineering the microstructure of the fiber network in gel materials.
Publisher: Elsevier BV
Date: 11-2016
Publisher: American Chemical Society (ACS)
Date: 22-05-2019
Abstract: Biomimetic human skinlike materials with preferably self-healing ability, high sensitivity for external stimuli, and good adhesiveness against erse substrates under a wide range of temperatures are of great importance in various applications such as wearable devices, human-motion devices, and soft robotics. However, most of the reported biomimetic human skinlike materials lack memory function, i.e., they cannot memorize the external stimuli once the stimuli disappear. This drawback hinders their applications in mimicking the human skin in real world. Here, a polyacrylamide/Au@polydopamine glycerol-water (GW) hydrogel has been designed to address this challenge. The as-prepared GW hydrogel exhibits a fast self-healing efficiency and good adhesiveness against erse substrates under a wide range of temperatures (from -15 to 37 °C). Additionally, our GW hydrogel also possesses good perceived ability for external stimuli and subtle/large human motions. Most importantly, resistance memory function has been realized based on our GW hydrogel. These outstanding properties make it potentially significant in mimicking the human skin in real world.
Publisher: American Vacuum Society
Date: 25-05-2016
DOI: 10.1116/1.4952451
Abstract: A silkworm cocoon is a porous biological structure with multiple protective functions. In the current work, the authors have used both experimental and numerical methods to reveal the unique moisture transfer characteristics through a wild Antheraea pernyi silkworm cocoon wall, in comparison with the long-domesticated Bombyx mori silkworm cocoon walls. The water vapor transmission and water vapor permeability (WVP) properties show that the A. pernyi cocoons exhibit directional moisture transfer behavior, with easier moisture transfer from inside out than outside in [e.g., the average WVP is 0.057 g/(h m bar) from inside out and is 0.034 g/(h m bar) from outside in]. Numerical analysis shows that the cubic mineral crystals in the outer section of the A. pernyi cocoon wall create a rough surface that facilitates air turbulence and promotes disturbance litude of the flow field, leading to lengthened water vapor transfer path and increased tortuosity of the moist air. It also indicates the vortex of water vapor can be generated in the outer section of cocoon wall, which increases the diffusion distance of water vapor and enhances the turbulence kinetic energy and turbulence eddy dissipation, signifying higher moisture resistance in the outer section. The difference in moisture resistance of the multiple A. pernyi cocoon layers is largely responsible for the unique directional moisture transfer behavior of this wild silkworm cocoon. These findings may inspire a biomimicry approach to develop novel lightweight moisture management materials and structures.
Publisher: Elsevier BV
Date: 05-2010
DOI: 10.1002/JPS.21993
Publisher: Elsevier BV
Date: 07-2002
Publisher: Elsevier BV
Date: 2018
Publisher: American Chemical Society (ACS)
Date: 20-09-2012
DOI: 10.1021/IE3015704
Publisher: Elsevier BV
Date: 03-2016
Publisher: Wiley
Date: 04-10-2006
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1TA09288J
Abstract: Inspired by a lotus leaf, a 3D carbon fibre-cotton-based conical water evaporator with tuneable water supply is designed. By changing the number of branch water paths, a balance between the water supply flux and evaporation rate is achieved.
Publisher: American Chemical Society (ACS)
Date: 05-2007
DOI: 10.1021/JP070600L
Abstract: An enhanced macromolecular nanofiber network and its implications have been developed by employing the understanding of its formation with an emphasis on its topological aspect. Using agarose aqueous solution as a typical ex le, the macromolecular nanofiber network of soft functional materials has been clearly visualized for the first time using the developed technique of field emission scanning electronic microscopy coupled with flash-freeze-drying. Both the systematic kinetic study and the image evidence indicates that the nanofiber network in soft functional materials such as agarose turns out to form through a self-expitaxial nucleation-controlled process. This new understanding enables us to engineer ultra functions of soft materials via nanofiber network architecture, which in turn opens up a new direction in nano fabrication.
Publisher: American Chemical Society (ACS)
Date: 18-03-2013
DOI: 10.1021/IE3033872
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C4CE00096J
Publisher: Wiley
Date: 23-08-2010
Publisher: Springer Science and Business Media LLC
Date: 07-08-2017
DOI: 10.1038/S41598-017-07502-3
Abstract: Molecular alignment underpins optical, mechanical, and thermal properties of materials, however, its direct measurement from volumes with micrometer dimensions is not accessible, especially, for structurally complex bio-materials. How the molecular alignment is linked to extraordinary properties of silk and its amorphous-crystalline composition has to be accessed by a direct measurement from a single silk fiber. Here, we show orientation mapping of the internal silk fiber structure via polarisation-dependent IR absorbance at high spatial resolution of 4.2 μ m and 1.9 μ m in a hyper-spectral IR imaging by attenuated total reflection using synchrotron radiation in the spectral fingerprint region around 6 μ m wavelength. Free-standing longitudinal micro-slices of silk fibers, thinner than the fiber cross section, were prepared by microtome for the four polarization method to directly measure the orientational sensitivity of absorbance in the molecular fingerprint spectral window of the amide bands of β -sheet polypeptides of silk. Microtomed lateral slices of silk fibers, which may avoid possible artefacts that affect spectroscopic measurements with fibers of an elliptical cross sections were used in the study. Amorphisation of silk by ultra-short laser single-pulse exposure is demonstrated.
Publisher: SAGE Publications
Date: 22-07-2016
Abstract: As a biological fibrous structure, silkworm cocoon provides multiple protective functionalities to safeguard the silk moth pupa’s metabolic activity. The mechanism of this protection could be adopted in clothing manufacture to provide more comfortable apparel. In this study, the thermal insulation properties of both domestic Bombyx mori ( B. mori) and wild Antheraea pernyi ( A. pernyi) cocoons were investigated under both warm and cold environmental conditions. Computational fluid dynamics models have been developed to simulate the heat transfer process through both types of cocoon wall structures. The simulation results show that the wild A. pernyi cocoon reduces the intensity of convection and heat flux between the environment and the cocoon interior and has higher wind resistance than its domestic counterpart. Compared with A. pernyi cocoon, the B. mori cocoon facilitates easy air transfer and decreases the temperature lag when the surrounding conditions are changed. The new knowledge has significant implications for developing biomimetic thermal functional materials.
Publisher: Wiley
Date: 16-09-2018
Abstract: Supramolecular assembly of chromophores with inherent resistance to aggregation-induced self-quenching is significant to applications such as chemical sensing and organic light emitting diodes (OLEDs). In this work, molecular gels with aggregation-induced emission (AIE) are constructed by simply coassembling AIE chromophores (electron donor or acceptor) with a nonfluorescent molecular gelator. The binary gels are fluorescent even at very low concentrations of the AIE chromophores, indicating that the rotation of their aromatic cores is restricted in the gel network. In tertiary gels, the fluorescence of the donor chromophore can be efficiently reduced by the acceptor chromophore through a combination of static and dynamic quenching process, via charge transfer from the donor to the acceptor. This work demonstrates a convenient approach to fabricate a supramolecular charge transfer system using an AIE donor and acceptor.
Publisher: Elsevier BV
Date: 11-2016
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7QM00084G
Abstract: An H-shaped, non-fullerene small molecular electron acceptor displayed promising optoelectronic properties and afforded an encouraging efficiency of 5.42%.
Publisher: Elsevier BV
Date: 2015
Publisher: Springer Science and Business Media LLC
Date: 05-12-2018
DOI: 10.1038/S41598-018-36114-8
Abstract: Polarised light imaging microscopy, with the addition of a liquid crystal (LC) phase retarder, was used to determine the birefringence of silk fibres with high (∼1 μ m) spatial resolution. The measurement was carried out with the silk fibres (the optical slow axis) and the slow axis of the LC-retarder set at parallel angles. The direct fit of the transmission data allowed for high fidelity determination of the birefringence Δn ≈ 1.63 × 10 −2 (with ∼2% uncertainty) of the brown silk fibre, ( Antheraea pernyi ) averaged over the wavelength range λ = (425–625) nm. By measuring retardance at four separate wavelengths, it was possible to determine the true value of the birefringence of a thicker s le when an optical path may include a large number of wavelengths. The numerical procedures and required hardware are described for the do-it-yourself assembly of the imaging polariscope at a fractional budget compared to commercial units.
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/CH13323
Abstract: A novel recyclable and flexible membrane was prepared for the removal of oil spills and organic dye pollutants, by functionalizing polyester textiles with reduced graphene oxide@ZnO nanocomposites using a layer-by-layer technique. The membrane showed efficient water/oil separation, and the amount of oil adsorbed by the membrane could be up to 23 times its own weight. The adsorption capacity was largely retained during many adsorption recycling cycles. The membrane also displayed highly efficient removal of a dye pollutant from water under simulated sunlight. The membrane maintained a near-original removal efficiency after five cycles of dye removal. This new type of membrane may find practical applications in the large-scale separation of organic pollutants from water, particularly in the field of oil spills clean-up and dye removal from industrial effluent.
Publisher: American Vacuum Society
Date: 24-07-2014
DOI: 10.1116/1.4890982
Abstract: Biological materials are hierarchically organized complex composites, which embrace multiple practical functionalities. As an ex le, the wild silkworm cocoon provides multiple protective functions against environmental and physical hazards, promoting the survival chance of moth pupae that resides inside. In the present investigation, the microstructure and thermal property of the Chinese tussah silkworm (Antheraea pernyi) cocoon in both warm and cold environments under windy conditions have been studied by experimental and numerical methods. A new computational fluid dynamics model has been developed according to the original fibrous structure of the Antheraea pernyi cocoon to simulate the unique heat transfer process through the cocoon wall. The structure of the Antheraea pernyi cocoon wall can promote the disorderness of the interior air, which increases the wind resistance by stopping most of the air flowing into the cocoon. The Antheraea pernyi cocoon is wind-proof due to the mineral crystals deposited on the outer layer surface and its hierarchical structure with low porosity and high tortuosity. The research findings have important implications to enhancing the thermal function of biomimetic protective textiles and clothing.
Publisher: American Chemical Society (ACS)
Date: 18-01-2013
DOI: 10.1021/AM302072U
Abstract: Shape conversions of silver nanoplates were realized by heating and subsequent light irradiation. The initial silver nanoprisms were transformed into silver nanodisks gradually in the process of heating, which was possibly achieved through dissolving and readsorption of silver atoms on the surface of silver nanoplates. Subsequently, under light irradiation, the heating induced silver nanodisks were reversed to silver nanoprisms in the same solution. The dissolved oxygen was found to play a pivotal role in the shape conversion from nanoprism to nanodisk. In addition to heating, deionized water could induce the shape conversion of silver nanoplates when it was added to precipitate of the initial silver nanoprisms after centrifugation. Citrate in solution is essential to the photoinduced shape conversion process. Transmission electron microscopy (TEM) and extinction spectroscopy results demonstrated that localized surface plasmon resonance (LSPR) properties of silver nanoplates were effectively tuned through shape conversion.
Publisher: Elsevier BV
Date: 03-2014
Publisher: Elsevier BV
Date: 07-2003
DOI: 10.1016/S0021-9797(03)00403-X
Abstract: A cloud-point extraction (CPE) process using the nonionic surfactant Tergitol 15-S-7, a secondary ethoxylated alcohol, to extract selected polycyclic aromatic hydrocarbons (PAHs) from aqueous solutions is investigated. The CPE process is facilitated at the ambient temperature, ca. 22 degrees C, by the reduction of the cloud-point temperature of the surfactant solution by addition of sodium sulfate. It is observed that the preconcentration factor could be enhanced either by increasing the salt concentration or by decreasing the initial surfactant concentration in the micellar solution. A high preconcentration factor of about 40 was achieved at 1 wt% surfactant concentration with the addition of 0.6 M Na(2)SO(4). It is also noted that the equilibrium partition coefficients of the model PAHs are nearly independent of surfactant concentrations, up to 3 wt%, in this study. Correlations between the equilibrium partition coefficients K(p) of the PAHs and their octanol-water partition coefficients K(ow), as well as K(p) and the molar volume V(x) of these PAHs, indicate that the partition processes of the PAHs in the CPE processes are mainly governed by their hydrophobic affinities to the surfactant aggregates. Furthermore, the effect of added Na(2)SO(4) on the equilibrium partition coefficients is also studied. It is shown that addition of more Na(2)SO(4) to the surfactant solution gives more partition of the PAHs into the surfactant-rich phase.
Publisher: AIP Publishing
Date: 09-2016
DOI: 10.1063/1.4962294
Abstract: Silk patterns in a film of amorphous water-soluble fibroin are created by tailored exposure to femtosecond-laser pulses (1030 nm/230 fs) without the use of photo-initiators. This shows that amorphous silk can be used as a negative tone photo-resist. It is also shown that water insoluble crystalline silk films can be precisely ablated from a glass substrate achieving the patterns of crystalline silk gratings on a glass substrate. Bio-compatible/degradable silk can be laser structured to achieve conformational transformations as demonstrated by infrared spectroscopy.
Publisher: Springer Science and Business Media LLC
Date: 15-02-2020
Publisher: Wiley
Date: 17-10-2008
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C2SM27065J
Publisher: AIP Publishing
Date: 21-08-2006
DOI: 10.1063/1.2338007
Abstract: An understanding of the physical hydrogel network formation has been obtained by dynamic rheological experiments. The evidence shows that the network formation turns out to be a nucleation-controlled process. It was found that there exists a critical temperature Tc fiber branching is greatly enhanced when the network formation is performed in the regime of T& Tc (T, the final setting temperature). This finding enables the authors to build significantly enhanced gel networks. So far G′ (elastic modulus) of the hydrogel network has been enhanced by 187% while the formation period can be greatly shortened to only 1∕20 of the previous process.
Publisher: MDPI AG
Date: 24-09-2019
DOI: 10.3390/APP9193991
Abstract: Orientational dependence of the IR absorbing amide bands of silk is demonstrated from two orthogonal longitudinal and transverse microtome slices with a thickness of only ∼100 nm. Scanning near-field optical microscopy (SNOM) which preferentially probes orientation perpendicular to the s le’s surface was used. Spatial resolution of the silk–epoxy boundary was ∼100 nm resolution, while the spectra were collected by a ∼10 nm tip. Ratio of the absorbance of the amide-II C-N at 1512 cm − 1 and amide-I C=O β -sheets at 1628 cm − 1 showed sensitivity of SNOM to the molecular orientation. SNOM characterisation is complimentary to the far-field absorbance which is sensitive to the in-plane polarisation. Volumes with cross sections smaller than 100 nm can be characterised for molecular orientation. A method of absorbance measurements at four angles of the slice cut orientation, which is equivalent to the four polarisation angles absorbance measurement, is proposed.
Publisher: Elsevier BV
Date: 07-2008
Publisher: American Chemical Society (ACS)
Date: 03-12-2021
DOI: 10.1021/ACSBIOMATERIALS.1C01228
Abstract: Hydrogels mimic the natural extracellular matrix in terms of their nanofibrous structure and large water content. However, the lack of a combination of properties including sufficient heterogeneity in the gel structure, intrinsic antimicrobial activity, and bioactivity limits the efficiency of hydrogels for tissue engineering applications. In this work, a hydrogel with a combination of these properties was fabricated by hybridizing silk fibroin with a low-molecular-weight peptide gelator. It was observed that silk fibroin and the peptide gelator assembled orthogonally in sequence. While the morphology of silk fibroin nanofibrils was not affected by the peptide gelator, silk fibroin promoted the formation of wider nanoribbons of the peptide gelator by modulating its nucleation and growth. Orthogonal assembly maintained the antimicrobial activity of the peptide gelator and the excellent biocompatibility of silk fibroin in the hybrid gel. The hybrid gel also demonstrated improved interactions with cells, an indicator of a higher bioactivity, possibly due to the heterogeneous double network structure.
Publisher: Elsevier BV
Date: 10-2018
DOI: 10.1016/J.COLSURFB.2018.06.066
Abstract: Highly ordered self-assembly of nanoparticles (NPs) in a large scale promises attractive potential in optical modulation of the NPs for illuminating, imaging and sensing applications. In this work, a type of multi-lamellar nanocomposite membranes composed of phospholipid multilayers and Si NPs sandwiched between each adjacent lipid layers was fabricated via a facile co-assembly method. X-ray reflectivity (XRR), grazing incident X-ray diffraction (GIXRD) and TEM measurements verified the highly ordered arrangement of NPs within the multilayers with a controlled in-plane inter-particle separation from ∼7 nm to ∼14 nm. Due to such an arrangement, the photoluminescence (PL) properties of the Si NPs were effectively modulated. Compared to the NPs in suspension or its pure film, the PL of the NPs in the membranes blue-shifted and remarkably narrowed, with the full-width-at-half-maximum (FWHM) value reduced from >110 nm of the pure Si NP film to below 43 nm. The radiative lifetime of the NPs was also significantly reduced from ∼16.7 ns to ∼3.3 ns depending on the inter-particle distance in the membrane. Meanwhile, the Si NPs within membranes maintained robust photostability under UV irradiation.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3TB01256E
Abstract: Mesoporous bioglass nanoparticles doped with strontium ions are prepared with a sol–gel method. The nanoparticles can significantly improve cell proliferation, migration, and tube formation in vitro , as well as skin wound healing in a mouse model.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/C9CP05488J
Abstract: The presence of unpaired electrons (radicals) due to structural defects is believed to contribute to the catalytic reactivity of carbon materials. Graphite oxide and graphene oxide (GO) consist of significant structural defects and hence are considered more reactive than graphite and graphene. However, the relationship between their radical content/reactivity and their physical and chemical structures remains unknown, which limits the fabrication of high efficiency carbon-based catalysts. In this work, we progressively oxidize graphite to achieve graphite oxide and GO with different levels of oxidation and different sizes. It is observed that a maximal radical content can be achieved on graphite oxide with a C/O ratio of ca. 3.0 and a thickness of around 50 nm. Such a graphite oxide contains about 45% of π bonds and 38% of oxygenated bonds, respectively. Thinner or thicker sheets have lower radical contents due to over or insufficient oxidation, respectively. Single GO sheets with high radical contents can only be produced through a combination of oxidation and reduction. The catalytic activity of the graphite/graphene oxide for phenol degradation was found to be linearly correlated to their radical contents. The observations are significant for the advancement of carbon-based metal-free catalysis.
Publisher: AIP Publishing
Date: 06-09-2005
DOI: 10.1063/1.2042552
Abstract: Three-dimensional fiber networks were created from an organogel system consisting mainly of elongated fibrils by using a nonionic surfactant as an additive. The presence of the surfactant molecules manipulates the network structure by enhancing the mismatch nucleation on the growing fiber tips. Both the fiber network structure and the rheological properties of the material can be finely tuned by changing the surfactant concentration, which provides a robust approach to the engineering of supramolecular soft functional materials.
Publisher: Springer Science and Business Media LLC
Date: 17-09-2015
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D2NR03417D
Abstract: Silk fibroin and bioglass coassemble to form a hybrid structure that is bioactive and mechanically strong.
Publisher: MDPI AG
Date: 29-10-2022
Abstract: Thermally conductive polyvinylidene fluoride (PVDF) composites were prepared by incorporating carbon fibers (CFs) with different lengths (286.6 ± 7.1 and 150.0 ± 2.3 µm) via cold pressing, followed by sintering. The length effects of the CF on the thermal conductivity, polymer crystallization behaviors, and mechanical properties of the PVDF composites were studied. The through-plane thermal conductivity of the PVDF composites increased significantly with the rise in CF loadings. The highest thermal conductivity of 2.89 W/(m∙K) was achieved for the PVDF composites containing 40 wt.% shorter CFs, ~17 times higher than that of the pure PVDF (~0.17 W/(m∙K)). The shorter CFs had more pronounced thermal conductive enhancement effects than the original longer CFs at higher filler loadings. CFs increased the storage modulus and the glass transition temperature of the PVDF. This work provides a new way to develop thermally conductive, mechanically, and chemically stable polymer composites by introducing CFs with different lengths.
Publisher: Elsevier BV
Date: 11-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C0CC04488A
Abstract: The formation of fiber networks and the resulting rheological properties of supramolecular soft materials are dramatically influenced when the volume of the system is reduced to a threshold. Unlike un-confined systems, the formation of fiber networks under volume confinement is independent of temperature and solute concentration.
Publisher: IOP Publishing
Date: 03-2017
Abstract: Combining the merits of delivery vectors with drug molecules is one of the key directions for development of efficient cancer monitoring and treatment techniques. In this work, a novel type of silicon based composite nanoparticles (NPs) with incorporated hydrophobic phthalocyanine molecules (Pc) was synthesized via a facile one-pot method. The as-synthesized Pc@Si NPs, with a small size of 4.2 ± 0.8 nm, have excellent dispersibility in water and good biocompatibility with cells, in addition to favorable photoluminescence and robust photostability even in cells. Moreover, the Pc@Si NPs show significant in vitro cancer cell killing and in vivo tumor inhibiting abilities upon near-infrared light exposure, due to the photodynamic therapy (PDT) effect of Pc. This work develops an efficient fluorescent PDT drug carrier moreover, the facile one-pot synthesis strategy may be used generally to prepare silicon-based composite NPs incorporated with erse hydrophobic drugs/diagnostic molecules for a wide range of biomedical applications.
Publisher: Elsevier BV
Date: 2015
Publisher: American Chemical Society (ACS)
Date: 13-01-2021
Publisher: Elsevier BV
Date: 02-2017
Publisher: American Chemical Society (ACS)
Date: 09-2020
Publisher: Elsevier BV
Date: 08-2013
DOI: 10.1016/J.MSEC.2013.03.051
Abstract: As a protective shell against environmental damage and attack by natural predators, the silkworm cocoon has outstanding mechanical properties. In particular, this multilayer non-woven composite structure can be exceptionally tough to enhance the chance of survival for silkworms while supporting their metabolic activity. Peel, out-of-plane compression and nano-indentation tests and micro-structure analysis were performed on four types of silkworm cocoon walls (domesticated Bombyx mori, semi-domesticated Antheraea assamensis and wild Antheraea pernyi and Antheraea mylitta silkworm cocoons) to understand the structure and mechanical property relationships. The wild silkworm cocoons were shown to be uniquely tough composite structures. The maximum work-of-fracture for the wild cocoons (A. pernyi and A. mylitta) was approximately 1000 J/m(2), which was almost 10 times the value for the domesticated cocoon (Bombyx mori) and 3~4 times the value for the semi-domesticated cocoon (A. assamensis). Calcium oxalate crystals were found to deposit on the outer surfaces of the semi-domesticated and wild cocoons. They did not show influence in enhancing the interlaminar adhesion between cocoon layers but exhibited much higher hardness than the cocoon pelades.
Publisher: SPIE-Intl Soc Optical Eng
Date: 09-2010
DOI: 10.1117/1.3502566
Abstract: Near-infrared laser-based microsurgery is promising for noninvasive cancer treatment. To make it a safe technique, a therapeutic process should be controllable and energy efficient, which requires the cancer cells to be identifiable and observable. In this work, for the first time we use a miniaturized nonlinear optical endomicroscope to achieve microtreatment of cancer cells labeled with gold nanorods. Due to the high two-photon-excited photoluminescence of gold nanorods, HeLa cells inside a tissue phantom up to 250 μm deep can be imaged by the nonlinear optical endomicroscope. This facilitates microsurgery of selected cancer cells by inducing instant damage through the necrosis process, or by stopping cell proliferation through the apoptosis process. The results indicate that a combination of nonlinear endomicroscopy with gold nanoparticles is potentially viable for minimally invasive cancer treatment.
Publisher: Elsevier BV
Date: 08-2021
Publisher: American Chemical Society (ACS)
Date: 14-05-2009
DOI: 10.1021/CG9000494
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8CC01779D
Abstract: Through the coupling of central and terminal naphthalene diimide functionalities, a unique non-fullerene electron acceptor, coded as N10 , was designed, synthesized, characterized and applied in solution-processable bulk-heterojunction devices.
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C0SM00873G
Publisher: Wiley
Date: 16-09-2018
Publisher: SAGE Publications
Date: 27-11-2015
Abstract: The wild Antheraea pernyi silkworm cocoon is a thin and light-weight structure, yet it has shown effective thermal insulation characteristics against extreme temperature fluctuations, which meet the demands of humans for lighter materials with higher thermal resistance. We present a two-dimensional computational fluid dynamics model of this unique fibrous cocoon structure to simulate the heat transfer process through the cocoon wall. The model is able to predict the temperature field inside the cocoon reasonably well. The results of the model also show that the mineral crystals present in the outer layers of the Antheraea pernyi cocoon can increase air flow resistance and decrease the effect of natural convection, which further reduces the heat transfer through the cocoon wall effectively. This has practical significance for the development of thermal functional textiles and composite structures.
Publisher: American Chemical Society (ACS)
Date: 30-11-2006
DOI: 10.1021/JP065101J
Abstract: A new approach of engineering of molecular gels was established on the basis of a nucleation-initiated network formation mechanism. A variety of gel network structures can be obtained by regulating the starting temperature of the sol-gel transition. This enables us to tune the network from the spherulitic domains pattern to the extensively interconnected fibrillar network. As the consequence of fibrous network structure turning, desirable rheological and other in-use properties of the materials can be obtained accordingly. This approach of micro-/nanostructural fabrication may open up a new route for micro-/nanofunctional materials engineering in general.
Publisher: American Chemical Society (ACS)
Date: 12-05-2010
DOI: 10.1021/CG100188W
Publisher: Wiley
Date: 10-08-2013
DOI: 10.1002/JBM.A.34871
Abstract: Nano-sized graphene and graphene oxide (GO) are promising for biomedical applications, such as drug delivery and photothermal therapy of cancer. It is observed in this work that the ultrafast reduction of GO nanoparticles (GONs) with a femtosecond laser beam creates extensive microbubbling. To understand the surface chemistry of GONs on the microbubble formation, the GONs were reduced to remove most of the oxygen-containing groups to get reduced GONs (rGONs). Microbubbling was not observed when the rGONs were irradiated by the laser. The instant collapse of the microbubbles may produce microcavitation effect that brings about localized mechanical damage. To understand the potential applications of this phenomenon, cancer cells labeled with GONs or rGONs were irradiated with the laser. Interestingly, the microbubbling effect greatly facilitated the destruction of cancer cells. When microbubbles were produced, the effective laser power was reduced to less than half of what is needed when microbubbling is absent. This finding will contribute to the safe application of femtosecond laser in the medical area by taking advantage of the ultrafast reduction of GONs. It may also find other important applications that need highly localized microcavitation effects.
Publisher: Beilstein Institut
Date: 23-04-2019
DOI: 10.3762/BJNANO.10.93
Abstract: The nanoscale composition of silk defining its unique properties via a hierarchial structural anisotropy needs to be analysed at the highest spatial resolution of tens of nanometers corresponding to the size of fibrils made of β-sheets, which are the crystalline building blocks of silk. Nanoscale optical and structural properties of silk have been measured from 100 nm thick longitudinal slices of silk fibers with ca. 10 nm resolution, the highest so far. Optical sub-wavelength resolution in hyperspectral mapping of absorbance and molecular orientation were carried out for comparison at IR wavelengths of 2–10 μm using synchrotron radiation. A reliable distinction of transmission changes by only 1–2% as the anisotropy of amide bands was obtained from nanometer-thin slices of silk.
Publisher: Royal Society of Chemistry (RSC)
Date: 2013
DOI: 10.1039/C3CP44312D
Abstract: The photoinduced growth reaction of silver nanoparticles was accelerated by reduced graphene oxide (RGO) produced from graphene oxide (GO) during the light irradiation process in aqueous solution. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy demonstrated that RGO was generated in the photoinduced process. The acceleration effect of RGO was investigated through monitoring the extinction spectra of silver nanoparticles during the synthesis process. Moreover, transmission electron microscopy (TEM) was employed to characterize the evolution of morphologies of silver nanoparticles at different irradiation times to demonstrate the effect of RGO. The results indicate that RGO accelerates the photoinduced synthesis of silver nanoparticles. It is proposed that the acceleration effect of RGO on the photoinduced reaction is attributed to the particular property of high electronic conductivity.
Publisher: Elsevier BV
Date: 12-2020
Publisher: American Chemical Society (ACS)
Date: 12-2005
DOI: 10.1021/JP054676Y
Abstract: The architecture of a biocompatible organogel formed by gelation of a small molecule organic gelator, N-lauroyl-L-glutamic acid di-n-butylamide, in isostearyl alcohol was investigated based on a supersaturation-driven crystallographic mismatch branching mechanism. By controlling the supersaturation of the system, the correlation length that determines the mesh size of the fiber network was finely tuned and the rheological properties of the gel were engineered. This approach is of considerable significance for many gel-based applications, such as controlled release of drugs that requires precise control of the mesh size. A direct cryo-transmission electron microscopy (TEM) imaging technique capable of preserving the network structure was used to visualize its nanostructure.
Publisher: Springer Science and Business Media LLC
Date: 22-04-2021
DOI: 10.1038/S41467-021-22673-4
Abstract: Artificial recapitulation of the hierarchy of natural protein fibers is crucial to providing strategies for developing advanced fibrous materials. However, it is challenging due to the complexity of the natural environment. Inspired by the liquid crystalline spinning of spiders, we report the development of natural silk-like hierarchical fibers, with bundles of nanofibrils aligned in their long-axis direction, by self-assembly of crystallized silk fibroin (SF) droplets. The formation of self-assembled SF fibers is a process of coalesced droplets sprouting to form a branched fibrous network, which is similar to the development of capillaries in our body. The as-assembled hierarchical SF fibers are highly bioactive and can significantly enhance the spreading and growth of human umbilical vein endothelial cells compared to the natural SF fibers. This work could help to understand the natural silk spinning process of spiders and provides a strategy for design and development of advanced fibrous biomaterials for various applications.
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0QM00041H
Abstract: Carbonyl-bridged triarylamine-based, three-dimensional non-fullerene acceptor ( R1 ) device: ITO/PEDOT:PSS/PTB7: R1 (1: 1.2)/Ca/Al PCE = 9.33%
Publisher: Elsevier BV
Date: 03-2019
Publisher: MDPI AG
Date: 28-03-2017
DOI: 10.3390/MA10040356
Publisher: Elsevier BV
Date: 11-2022
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C6QM00219F
Abstract: Cellular orientation and migration are mediated by internalized Fe 3 O 4 nanoparticles with an external magnetic field in a particle-concentration dependent manner.
Publisher: Springer Science and Business Media LLC
Date: 07-11-2017
DOI: 10.1038/S41598-017-15395-5
Abstract: Today’s electronic devices are fabricated using highly toxic materials and processes which limits their applications in environmental sensing applications and mandates complex encapsulation methods in biological and medical applications. This paper proposes a fully resorbable high density bio-compatible and environmentally friendly solution processable memristive crossbar arrays using silk fibroin protein which demonstrated bipolar resistive switching ratio of 10 4 and possesses programmable device lifetime characteristics before the device gracefully bio-degrades, minimizing impact to environment or to the implanted host. Lactate dehydrogenase assays revealed no cytotoxicity on direct exposure to the fabricated device and support their environmentally friendly and biocompatible claims. Moreover, the correlation between the oxidation state of the cations and their tendency in forming conductive filaments with respect to different active electrode materials has been investigated. The experimental results and the numerical model based on electro-thermal effect shows a tight correspondence in predicting the memristive switching process with various combinations of electrodes which provides insight into the morphological changes of conductive filaments in the silk fibroin films.
Publisher: Elsevier BV
Date: 12-2016
DOI: 10.1016/J.FOODCHEM.2016.05.162
Abstract: Konjac glucomannan - tungsten (KGM-T) gels were successfully prepared under DC electric fields, in the presence of sodium tungstate. The textural properties and microstructure of the gels were investigated by Texture Analyzer, Rheometer and SEM. Based on the response surface methodology (RSM) results, the optimum conditions for KGM-T gel springiness is 0.32% sodium tungstate concentration, 0.54% KGM concentration, 24.66V voltage and 12.37min treatment time. Under these conditions, the maximum springiness value of KGM-T gel is 1.21mm. Steady flow measurement indicated that KGM-T gel showed characteristic non-Newtonian pseudoplastic behaviour, with low flow behaviour indexes in the shear thinning region. SEM demonstrated the porosity of the freeze-dried s les. These findings may pave the way to use DC electric fields for the design and development of KGM gels and to apply KGM gels for practical applications.
Publisher: American Chemical Society (ACS)
Date: 17-03-2009
DOI: 10.1021/JP8035023
Abstract: A finite element method based on ABAQUS is employed to examine the correlation between the microstructure and the elastic response of planar Cayley treelike fiber networks. It is found that the elastic modulus of the fiber network decreases drastically with the fiber length, following the power law. The power law of elastic modulus G' vs the correlation length xi obtained from this simulation has an exponent of -1.71, which is close to the exponent of -1.5 for a single-domain network of agar gels. On the other hand, the experimental results from multidomain networks give rise to a power law index of -0.49. The difference between -1.5 and -0.49 can be attributed to the multidomain structure, which weakens the structure of the overall system and therefore suppresses the increase in G'. In addition, when the aspect ratio of the fiber is smaller than 20, the radius of the fiber cross-section has a great impact on the network elasticity, while, when the aspect ratio is larger than 20, it has almost no effect on the elastic property of the network. The stress distribution in the network is uniform due to the symmetrical network structure. This study provides a general understanding of the correlation between microscopic structure and the macroscopic properties of soft functional materials.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3TA02131A
Abstract: A sodium alginate-based hemisphere with centripetal conical channels loaded with CaCl 2 crystals and coated with a photothermal layer was designed for moisture absorption, unidirectional water transfer and solar-driven water evaporation.
Publisher: Elsevier BV
Date: 02-2009
DOI: 10.1016/J.JHAZMAT.2008.05.019
Abstract: Biodegradation of three nonionic surfactants, Tergitol 15-S-X (X=7, 9 and 12), and their effects on the biodegradation of phenanthrene by marine bacteria, Neptunomonas naphthovorans, were studied. The experimental outcomes could be fit well with the first-order biodegradation kinetics model. It was observed that the biodegradability of these surfactants decreased with an increase in the chain length of the hydrophilic moiety of the surfactant. When surfactant concentrations initially present were less than 250mgcarbon/L, biodegradability of Tergitol 15-S-X surfactants is around 0.3. Reduced biodegradability of Tergitol 15-S-7 and Tergitol 15-S-9 was observed when their concentrations initially present were increased to 322 and 371mgcarbon/L, respectively. In general, biodegradation of phenanthrene was enhanced with increasing solubilization of phenanthrene by these surfactants. However, with the same initial concentration of phenanthrene, biodegradability of phenanthrene was found to decrease with an increase in surfactant concentration. For these three surfactants, more than 80% of the phenanthrene was degraded when surfactant concentrations initially present were 200mg/L. However, less than 30% of phenanthrene could be degraded, if initial surfactant concentrations were increased to 1000mg/L. Interestingly, the concurrent biodegradation of the surfactants reduced their effective concentrations for micelle formation and, hence, contribute to the higher bioavailability of phenanthrene by gradually releasing phenanthrene molecules into the aqueous phase.
Publisher: Springer Science and Business Media LLC
Date: 19-01-2021
Publisher: American Chemical Society (ACS)
Date: 18-03-2006
DOI: 10.1021/JP054531R
Abstract: Low-molecular mass organic gelators self-organizing into three-dimensional fiber networks within organic solvents have attracted much attention in recent years. However, to date, how the microstructure of fiber network is formed in a gelation process and the key factors that govern the topological structure of a gel network remain to be determined. In this work, we address these issues by investigating the in situ formation of the gel networks in the N-lauroyl-l-glutamic acid di-n-butylamide (GP-1) ropylene glycol (PG) system. By using optical microscopy, the time evolution of the gel network microstructure was investigated under various supersaturation conditions. It is found that supersaturation is one of the key factors that govern the topological structure of a gel network. In particular, the creation of the junctions turns out to be supersaturation-dependent. The rheological experiments further revealed the correlation between topological structure and mechanical properties. It suggests that the rheological properties can be effectively modified by tuning the microstructure topology of the gel network. Our results reported here provide new physical insight into the formation kinetics of a molecular gel. Furthermore, this work could be important in constructing and engineering a supramolecular structure for the purpose of applications.
Publisher: MDPI AG
Date: 10-10-2018
DOI: 10.3390/MA11101929
Abstract: After platinum nanoparticles (PtNPs) were in-situ synthesized on silk fabrics through heat treatment, it was determined that the treatment of the silk fabrics with PtNPs imparted multiple functions, including coloring, catalysis, and antibacterial activity. The formation of PtNPs on fabrics was affected by the Pt ion concentration, pH value of solution, and reaction temperature. Acidic condition and high temperature were found to facilitate the formation of PtNPs on silk. The color strength of silk fabrics increased with the concentration of Pt ions. The PtNP treated silk fabrics exhibited reasonably good washing color fastness and excellent rubbing color fastness. The morphologies and chemical components of the treated silk fabrics were analyzed using scanning electron microscopy and X-ray photoelectron spectroscopy. The PtNP treated silk fabric exhibited significant catalytic function and a notable antibacterial effect against Escherichia coli (E. coli).
Publisher: Elsevier BV
Date: 05-2017
Publisher: Elsevier BV
Date: 11-2019
Publisher: American Chemical Society (ACS)
Date: 03-07-2020
Publisher: American Chemical Society (ACS)
Date: 25-07-2017
DOI: 10.1021/ACS.JPCLETT.7B01557
Abstract: It is known that hierarchical structure plays a key role in many unique material properties such as self-cleaning effect of lotus leaves and the antifogging property of the compound eyes of mosquitoes. This study reports a series of highly ordered mesoporous Nafion membranes with unique hierarchical structural features at the nanometer scale. Using NMR, we show for the first time that, at low RH conditions, the proton in the ionic domains migrates via a surface diffusion mechanism and exhibits approximately 2 orders of magnitude faster transport than that in the nanopores, whereas the nanopores play a role of reservoir and maintain water and thereby conductivity at higher temperature and lower humidities. Thereby creating hierarchical nanoscale structures is a feasible and promising strategy to develop PEMs that would enable efficient electrochemical performance in devices such as fuel cells, even in the absence of high humidity and at elevated temperatures.
Publisher: Elsevier BV
Date: 08-2017
Publisher: American Scientific Publishers
Date: 05-2008
DOI: 10.1166/JNN.2008.502
Abstract: Selenium-polypyrrole core–shell nanoparticles are fabricated by an in-situ polymerization process and functionalized with transferrin for targeting and imaging of human cervical cancer cells. The shell thickness and chemical composition of the as-synthesized particles can be manipulated by controlling the precursor concentration. The presence of the polymer layer can greatly increase the thermal stability of the selenium nanoparticles. The presence of transferrin molecules on the surface of the core–shell nanoparticles can significantly enhance their cellular uptake. The tranferrin-conjugated core–shell nanoparticles can be potentially used for the targeting and imaging of cancer cells.
Publisher: Elsevier BV
Date: 02-2015
Publisher: American Chemical Society (ACS)
Date: 09-08-2013
DOI: 10.1021/JP402826N
Abstract: Environmentally responsive materials are attractive for advance biomedicine applications such as controlled drug delivery and gene therapies. Recently, we have introduced the fabrication of a novel type of stimuli-sensitive lipogel composite consisting of poly(N-isopropylacrylamide) (pNIPAM) microgel particles and lipids. In this study, we demonstrated the temperature-triggered drug release behavior and the tunable drug loading and release capacities of the lipogel. At room temperature (22 °C), no calcein was released from the lipogel over time. At body temperature (37 °C), the release process was significantly promoted lipids in the lipogel acted as drug holders on the pNIPAM scaffold carrier and prolonged the calcein release process from 10 min to 2 h. Furthermore, the loading and release of calcein could be effectively controlled by modulating the relative amount of lipids incorporated in the lipogel, which can be realized by the salt-induced lipid release of the lipogel.
Publisher: Springer Science and Business Media LLC
Date: 02-07-2018
DOI: 10.1038/S41598-018-28313-0
Abstract: Extrusion processing of carbon tubes can be problematic due to their poor interfacial interactions with polymeric matrices. Surface chemical modification of carbon tubes can be utilized to create bonding sites to form networks with polymer chains. However, chemical reactions resulting in intermolecular primary bonding limit processability of extrudate, since they cause unstable rheological behaviour, and thus decrease the stock holding time, which is determinative in extrusion. This study presents a method for the synthesis of carbon microtubes with physically modified surface area to improve the filler and matrix interfacial interactions. The key concept is the formation of a nanogrooved topography, through acoustic cavitation on the surface of processing fibres. The effect of nanogrooving on roughness parameters is described, along with the role of surface modified carbon tubes on rheological behaviour, homogeneity, and coherency of extrudate. The measurements showed that nanogrooving increases the surface area of carbon microtubes, as a result, die swelling of the extrudate is reduced. Furthermore, after solidification, the mechanical strength of composite is reinforced due to stronger interactions between nanogrooved carbon tubes and polymer matrix.
Publisher: Springer Science and Business Media LLC
Date: 15-06-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9QM00129H
Abstract: A non-fullerene acceptor, W8 , based on tetraphenylethylene and naphthalene diimide ITO/PEDOT:PSS/PTB7: W8 (1 : 1.2 D : A w/w)/Ca/Al PCE = 8.58%.
Publisher: IOP Publishing
Date: 07-2019
DOI: 10.1088/0253-6102/71/7/887
Abstract: Pore-forming peptides have promising potentials for biomedical uses due to their ability to permeabilize cell membranes. However, to molecularly engineer them for practical applications is still blocked by the poor understanding of the specific roles of in idual residues in peptides’ activity. Herein, using an advanced computational approach that combines Coarse-Grained molecular dynamics and well-tempered metadynamics, the membrane activities of melittin, a representative pore-forming peptide, and its gain-of-function variants, are characterized from the kinetics and thermodynamics perspectives. Unbiased simulations elucidate the molecular details of peptide-induced membrane poration during which, some vital intermediate states, including the aggregation and U-shape configuration formation of peptides in the membrane, are observed and further applied as collective variables to construct the multi-dimensional free energy landscapes of the peptide-membrane interactions. Such a combination of kinetic and thermodynamic descriptions of the interaction process provides crucial information of residue-specialized contribution in chain conformation and consequently membrane perforation ability of the peptide. It is found that residues at the kink part (e.g. Thr) determine the chain flexibility and U-shape bending of the peptide, while residues near the C-terminus (e.g. Arg and Lys) are responsible for recruiting neighboring peptides for inter-molecular cooperation the probable reaction pathway and the poration efficiency are consequently regulated. These results are helpful for a comprehensive understanding of the complicated molecular mechanism of pore-forming peptides and pave the way to rationally design and/or engineer the peptides for practical applications .
Publisher: Elsevier BV
Date: 2017
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6RA05538A
Abstract: A novel, NDI-based non-fullerene electron acceptors ( R1 , R2 ) for solution-processable bulk-heterojunction, displayed good thermal stability and afforded 2.24% power conversion efficiency.
Publisher: Elsevier BV
Date: 07-2018
Publisher: Elsevier BV
Date: 09-2016
DOI: 10.1016/J.JCIS.2016.06.030
Abstract: Silkworm silk fibers are core-shell composites of fibroin and sericin proteins. Studying the interactions between fibroin and sericin is essential for understanding the properties of these composites. It is observed that compared to the domestic silk cocoon Bombyx mori (B. mori), the adhesion between fibroin and sericin from the wild silk cocoon, Antheraea pernyi (A. pernyi), is significantly stronger with a higher degree of heterogeneity. The adsorption of A. pernyi sericin on its fibroin is almost twice the value for B. mori sericin on fibroin, both showing a monolayer Langmuir adsorption. (1)H NMR and FTIR studies demonstrate on a molecular level the stronger interactions and the more intensive complex formation between A. pernyi fibroin and sericin, facilitated by the hydrogen bonding between glycine and serine. The findings of this study may help the design of composites with superior interfacial adhesion between different components.
Publisher: Elsevier BV
Date: 11-2023
Publisher: American Chemical Society (ACS)
Date: 27-08-2013
DOI: 10.1021/LA4023085
Abstract: This paper describes a strategy of fabricating a new class of nano hybrid particles in terms of the "nanocages" of reactive molecular matrices/networks. The concept is to design molecular matrices functionalized with particular reactive groups, which can on-site synthesize and fix nanoparticles at the designated positions of the molecular networks. The cages of the molecular networks impose the confinement and protection to the nanoparticles so that the size and the stability of nano hybrid particles can be better controlled. To this end, polyamide network polymers (PNP) were synthesized and adopted as the reactive molecular cages for the control of silver nanoparticles formation. It follows that the silver nano hybrid particles fabricated by this method have an average diameter of 4.34 nm much smaller than any other or similar methods ie by a hyperbranched polyamide polymer (HB-PA). As per our design, the size of the silver nano hybrid particles can also be tuned by controlling the molar ratio between silver ions and the functional groups in the polymeric matrices. The silver nano hybrid particles reveal the substantially enhanced stability in aqueous solutions, which gives rise to the long stable performance of localized surface plasmon resonance. As the nano hybrid particles display long eminent nanoeffects, they exert broad implications for a wide range of applications such as biomedicine, catalysis, and optoelectronics.
Publisher: MDPI AG
Date: 23-02-2009
DOI: 10.3390/MA2010076
Publisher: American Chemical Society (ACS)
Date: 24-05-2021
Publisher: Elsevier BV
Date: 02-2005
Start Date: 2014
End Date: 2017
Funder: Australian Research Council
View Funded ActivityStart Date: 2012
End Date: 2014
Funder: Australian Research Council
View Funded ActivityStart Date: 2021
End Date: 2024
Funder: Australian Research Council
View Funded ActivityStart Date: 2021
End Date: 2023
Funder: Australian Research Council
View Funded ActivityStart Date: 2014
End Date: 2018
Funder: Australian Research Council
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