Aims: Polymethylsilsesquioxane (PMQS) is a silicone derivative that serves as a skin conditioning... more Aims: Polymethylsilsesquioxane (PMQS) is a silicone derivative that serves as a skin conditioning agent and moisturizer in cosmetics. The objective of this study is to identify the effect of different concentrations PMSQ (0.12, 0.20 and 0.35 wt %) on liquid foundation (LF) and find the optimized composition in vitro. Study Design: Structural and morphological features of the examined nano/micro-sized samples were investigated by different methods. Place and Duration of Study: Hacettepe University, Department of Physics Engineering, X-Rays Laboratory, between September 2017 and September 2019. Methodology: Micro/nano scale structural and morphological properties of samples were investigated by means of a multi-methodological approach based on Small‐ and/or Wide‐Angle X‐ray Scattering (SWAXS), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDX), Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) Spectroscopy and UV-vis Spectroscopy. The LF...
This study was focused on cyclohexene (CH) mid-chain functional polymer of polystyrene (PSt-CH-PS... more This study was focused on cyclohexene (CH) mid-chain functional polymer of polystyrene (PSt-CH-PSt) because of its potential application in nanotechnology and its possible usage in hierarchical structures. Molecular and nano scale structural characterizations and thermal behavior of the powder form PSt-CH-PSt functional polymer were carried out by FTIR, SAXS, XRD and DSC methods. Solutions of PSt-CH-PSt in tetrahydrofuran and chloroform were also investigated by SAXS and FTIR. The stable one type nano particles which have oblate core-shell shape were determined in powder form and in solution of PSt-CH-PSt. The self-assembly kinetics of the polymer indicate that the mid chain part location in oblate core shell aggregations may be controlled by polar aprotic THF and nonpolar CLF solvent effects. Exponential decreasing in oblate shell volumes of PSt-CH-PSt nano globules in THF as a function of temperature was also determined by SAXS.
Langmuir : the ACS journal of surfaces and colloids, Jun 28, 2016
Characterization of amyloid-like aggregates through converging approaches can yield deeper unders... more Characterization of amyloid-like aggregates through converging approaches can yield deeper understanding of their complex self-assembly mechanisms and the nature of their strong mechanical stability, which may in turn contribute to the design of novel supramolecular peptide nanostructures as functional materials. In this study, we investigated the coassembly kinetics of oppositely charged short amyloid-inspired peptides (AIPs) into supramolecular nanostructures by using confocal fluorescence imaging of thioflavin T binding, turbidity assay and in situ small-angle X-ray scattering (SAXS) analysis. We showed that coassembly kinetics of the AIP nanostructures were consistent with nucleation-dependent amyloid-like aggregation, and aggregation behavior of the AIPs was affected by the initial monomer concentration and sonication. Moreover, SAXS analysis was performed to gain structural information on the size, shape, electron density, and internal organization of the coassembled AIP nanos...
Synthetic vaccines utilize viral signatures to trigger immune responses. Although the immune resp... more Synthetic vaccines utilize viral signatures to trigger immune responses. Although the immune responses raised against the biochemical signatures of viruses are well characterized, the mechanism of how they affect immune response in the context of physical signatures is not well studied. In this work, we investigated the ability of zero- and one-dimensional self-assembled peptide nanostructures carrying unmethylated CpG motifs (signature of viral DNA) for tuning immune response. These nanostructures represent the two most common viral shapes, spheres and rods. The nanofibrous structures were found to direct immune response towards Th1 phenotype, which is responsible for acting against intracellular pathogens such as viruses, to a greater extent than nanospheres and CpG ODN alone. In addition, nanofibers exhibited enhanced uptake into dendritic cells compared to nanospheres or the ODN itself. The chemical stability of the ODN against nuclease-mediated degradation was also observed to ...
Various experimental methods (XRD, FTIR, SAXS, DLS and SEM) were used to investigate structures o... more Various experimental methods (XRD, FTIR, SAXS, DLS and SEM) were used to investigate structures of the silk samples weaved by spiders in Turkey. Silk samples were collected from the natural habitats belonging to the spider species (i.e., Near Salt Lake/şereflikoçhisar, İvriz Dam/Ereǧli-Konya, Karataş Lake/Burdur and several locations in Black Sea Region of Turkey). Among all collected species, Araneidae(Araneus angulatus, Argiope bruennichi, Argiope lobata, Larinoides cornutus), Eresidae(Eresus cinnaberinus), Agelenidae(Agelena labyrinthica), Oecobidae(Uroctea durandi), Miturgidae(Cheiracanthium erraticum), Salticidae(Heliophanus flavipes, Philaeus chrysops), Theridiidae(Steatoda paykulliana)and Gnaphosidae were found significant amongst other spider species. Structural differences and similarities of these species were reported. Diameter range of draglines, inter crystallite distance of nano-size structures, mean size range of nano-structure aggregations, crystallite size range, in...
ABSTRACT The study performs preparation of the precursor thin films with MgO doped ZnO nanocrysta... more ABSTRACT The study performs preparation of the precursor thin films with MgO doped ZnO nanocrystalline ceramics by electrospinning technique and their characterizations by small and wide angle X-ray scattering methods. The prepared films on Si and commercial glass wafers as nanoceramic mats were calcined at 320, 340, 360 and 380 C. The role of the annealing conditions on the morphological changes and uniformity of the films was also investigated. Results show that, the thermal process and choice of the wafer are critical for film morphology at the nano and atomic scales through the network shrinkage and crystallization, respectively. Samples show mono/polydisperse isolated nanoclusters/regular lamellar distributions/and embedded aggregations.
Aims: Polymethylsilsesquioxane (PMQS) is a silicone derivative that serves as a skin conditioning... more Aims: Polymethylsilsesquioxane (PMQS) is a silicone derivative that serves as a skin conditioning agent and moisturizer in cosmetics. The objective of this study is to identify the effect of different concentrations PMSQ (0.12, 0.20 and 0.35 wt %) on liquid foundation (LF) and find the optimized composition in vitro. Study Design: Structural and morphological features of the examined nano/micro-sized samples were investigated by different methods. Place and Duration of Study: Hacettepe University, Department of Physics Engineering, X-Rays Laboratory, between September 2017 and September 2019. Methodology: Micro/nano scale structural and morphological properties of samples were investigated by means of a multi-methodological approach based on Small‐ and/or Wide‐Angle X‐ray Scattering (SWAXS), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM/EDX), Attenuated Total Reflection-Fourier Transform Infrared (ATR-FTIR) Spectroscopy and UV-vis Spectroscopy. The LF...
This study was focused on cyclohexene (CH) mid-chain functional polymer of polystyrene (PSt-CH-PS... more This study was focused on cyclohexene (CH) mid-chain functional polymer of polystyrene (PSt-CH-PSt) because of its potential application in nanotechnology and its possible usage in hierarchical structures. Molecular and nano scale structural characterizations and thermal behavior of the powder form PSt-CH-PSt functional polymer were carried out by FTIR, SAXS, XRD and DSC methods. Solutions of PSt-CH-PSt in tetrahydrofuran and chloroform were also investigated by SAXS and FTIR. The stable one type nano particles which have oblate core-shell shape were determined in powder form and in solution of PSt-CH-PSt. The self-assembly kinetics of the polymer indicate that the mid chain part location in oblate core shell aggregations may be controlled by polar aprotic THF and nonpolar CLF solvent effects. Exponential decreasing in oblate shell volumes of PSt-CH-PSt nano globules in THF as a function of temperature was also determined by SAXS.
Langmuir : the ACS journal of surfaces and colloids, Jun 28, 2016
Characterization of amyloid-like aggregates through converging approaches can yield deeper unders... more Characterization of amyloid-like aggregates through converging approaches can yield deeper understanding of their complex self-assembly mechanisms and the nature of their strong mechanical stability, which may in turn contribute to the design of novel supramolecular peptide nanostructures as functional materials. In this study, we investigated the coassembly kinetics of oppositely charged short amyloid-inspired peptides (AIPs) into supramolecular nanostructures by using confocal fluorescence imaging of thioflavin T binding, turbidity assay and in situ small-angle X-ray scattering (SAXS) analysis. We showed that coassembly kinetics of the AIP nanostructures were consistent with nucleation-dependent amyloid-like aggregation, and aggregation behavior of the AIPs was affected by the initial monomer concentration and sonication. Moreover, SAXS analysis was performed to gain structural information on the size, shape, electron density, and internal organization of the coassembled AIP nanos...
Synthetic vaccines utilize viral signatures to trigger immune responses. Although the immune resp... more Synthetic vaccines utilize viral signatures to trigger immune responses. Although the immune responses raised against the biochemical signatures of viruses are well characterized, the mechanism of how they affect immune response in the context of physical signatures is not well studied. In this work, we investigated the ability of zero- and one-dimensional self-assembled peptide nanostructures carrying unmethylated CpG motifs (signature of viral DNA) for tuning immune response. These nanostructures represent the two most common viral shapes, spheres and rods. The nanofibrous structures were found to direct immune response towards Th1 phenotype, which is responsible for acting against intracellular pathogens such as viruses, to a greater extent than nanospheres and CpG ODN alone. In addition, nanofibers exhibited enhanced uptake into dendritic cells compared to nanospheres or the ODN itself. The chemical stability of the ODN against nuclease-mediated degradation was also observed to ...
Various experimental methods (XRD, FTIR, SAXS, DLS and SEM) were used to investigate structures o... more Various experimental methods (XRD, FTIR, SAXS, DLS and SEM) were used to investigate structures of the silk samples weaved by spiders in Turkey. Silk samples were collected from the natural habitats belonging to the spider species (i.e., Near Salt Lake/şereflikoçhisar, İvriz Dam/Ereǧli-Konya, Karataş Lake/Burdur and several locations in Black Sea Region of Turkey). Among all collected species, Araneidae(Araneus angulatus, Argiope bruennichi, Argiope lobata, Larinoides cornutus), Eresidae(Eresus cinnaberinus), Agelenidae(Agelena labyrinthica), Oecobidae(Uroctea durandi), Miturgidae(Cheiracanthium erraticum), Salticidae(Heliophanus flavipes, Philaeus chrysops), Theridiidae(Steatoda paykulliana)and Gnaphosidae were found significant amongst other spider species. Structural differences and similarities of these species were reported. Diameter range of draglines, inter crystallite distance of nano-size structures, mean size range of nano-structure aggregations, crystallite size range, in...
ABSTRACT The study performs preparation of the precursor thin films with MgO doped ZnO nanocrysta... more ABSTRACT The study performs preparation of the precursor thin films with MgO doped ZnO nanocrystalline ceramics by electrospinning technique and their characterizations by small and wide angle X-ray scattering methods. The prepared films on Si and commercial glass wafers as nanoceramic mats were calcined at 320, 340, 360 and 380 C. The role of the annealing conditions on the morphological changes and uniformity of the films was also investigated. Results show that, the thermal process and choice of the wafer are critical for film morphology at the nano and atomic scales through the network shrinkage and crystallization, respectively. Samples show mono/polydisperse isolated nanoclusters/regular lamellar distributions/and embedded aggregations.
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