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The dynamics of the thermodynamic equilibrium establishment in the aqueous solutions of alcohols in a vicinity of specific points is studied on the basis of dilute aqueous solutions of glycerol. At the molar fractions of alcohol 𝑥 ∼ 0.05, the systems concerned reveal characteristic anomalies testifying to the presence of structural phase transitions. However, the unreliable reproducibility of anomalous light scattering, a phenomenon typical of aqueous alcohol solutions, makes this conclusion debatable. In this work, it was shown that the parameters of aqueous glycerol solutions, which are determined with the help of light scattering phenomenon, become stable only in a certain time interval after the solution preparation. The typical dimensions of optical non-uniformities, the coefficients of scattered light depolarization, and the asymmetry of scattering indicatrix have been found as functions of the time elapsed since the solution preparation.K e y w o r d s: anomalous light scattering, dilute alcohol aqueous solutions, glycerol, thermodynamic equilibrium.

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Nowadays, determining the disassembly mechanism of amyloids under nanomaterials action is a crucial issue for their successful future use in therapy of neurodegenerative and overall amyloid-related diseases. In this study, the antiamyloid disassembly activity of fullerenes C60 and C70 dispersed in 1-methyl-2-pyrrolidinone (NMP) toward amyloid fibrils preformed from lysozyme and insulin was investigated using a combination of different experimental techniques. Thioflavin T fluorescence assay and atomic force microscopy were applied for monitoring of disaggregation activity of fullerenes. It was demonstrated that both types of fullerene-based complexes are very effective in disassembling preformed fibrils, and characterized by the low apparent half-maximal disaggregation concentration (DC50) in the range of ∼22–30 μg mL–1. Small-angle neutron scattering was employed to monitor the different stages of the disassembly process with respect to the size and morphology of the aggregates. Based on the obtained results, a possible disassembly mechanism for amyloid fibrils interacting with fullerene/NMP complexes was proposed. The study is a principal step in understanding of the fullerenes destruction mechanism of the protein amyloids, as well as providing valuable information on how macromolecules can be engineered to disassemble unwanted amyloid aggregates by different mechanisms.

At present, both native and immobilized nanoparticles are of great importance in many areas of science and technology. In this paper, we have studied magnetic iron oxide nanoparticles and their aggregates bound on woven cotton textiles employing two simple modification procedures. One modification was based on the treatment of textiles with perchloric-acidstabilized magnetic fluid diluted with methanol followed by drying. The second procedure was based on the microwave-assisted conversion of ferrous sulfate at high pH followed by drying. The structure and functional properties of these modified textiles were analyzed in detail. Scanning electron microscopy of native and modified textiles clearly showed the presence of iron oxide nanoparticles on the surface of the modified cotton fibers. All of the modified textile materials exhibited light to dark brown color depending on the amount of the bound iron oxide particles. Magnetic measurements showed that the saturation magnetization values reflect the amount of magnetic nanoparticles present in the modified textiles. Small-angle X-ray and neutron scattering measurements were conducted for the detailed structural characterization at the nanoscale of both the native and magnetically modified textiles, and different structural organization of nanoparticles in the two kinds of textile samples were concluded. The textile-bound iron oxide particles exhibited peroxidase-like activity when the N,N-diethyl-p-phenylenediamine sulfate salt was used as a substrate; this nanozyme activity enabled rapid decolorization of crystal violet in the presence of hydrogen peroxide. The deposition of a sufficient amount of iron oxide particles on textiles enabled their simple magnetic separation from large volumes of solutions; if necessary, the magnetic response of the modified textiles can be simply increased by incorporation of a piece of magnetic iron wire. The simplicity of the immobilized nanozyme preparation and the low cost of all the precursors enable its widespread application, such as decolorization and degradation of selected organic dyes and other important pollutants. Other types of textilebound nanozymes can be prepared and used as low-cost catalysts for a variety of applications.