Nanotechnologies in Russia最新文献

Unithiol, as a biologically active ligand that forms stable complexes with metals, is of significant interest and requires systematic research when designing efficient medicinal agents. The accelerated “green” synthesis of a tungsten complex with unithiol as a ligand is carried out using two methods: ultrasonic and microwave. The precursors to this reaction are an extract of Picea pungens Engelm. spruce needles as a natural source of presumably bioactive unithiol and sodium tungstate; the reaction duration is 15 min. X-ray absorption spectra (XANES) near the L₃ edge of tungsten absorption for a tungsten–unithiol complex are obtained and qualitatively analyzed for the first time.

It is known that the catalytic properties of materials based on bimetallic PtCu nanoparticles depend on both the composition and the distribution of atoms in these particles. Therefore, the development of new materials with improved catalytic properties requires the application of an accurate and reliable experimental method for determining the architecture of nanoparticles (NPs) (random solid solution, Janus, core–shell or “gradient”). Our previous study demonstrated through machine-learning simulations that the architecture of single bimetallic nanoparticles can be determined using accurate theoretically calculated paired atomic radial distribution functions (RDFs), which can also be obtained from the most common sources of NP structural information, such as the X-ray absorption spectroscopy (XAS) and X-ray diffraction (XRD) techniques. This work is a logical continuation of the research mentioned above and is devoted to a theoretical study of the influence of errors in determining the RDFs, as well as the influence of the size and composition distributions of nanoparticles on the possibility of determining the architecture of nanoparticles from their RDFs.

Modern microfluidic technologies play an important role in scientific research, medicine, pharmacology, ecology, and biotechnologies and nanotechnologies. The significance of microfluidic processes within bioinspired technologies and their potential for the development of new methods and applications is considered. An important advantage of microfluidic technologies is the ability to work with very small volumes of liquid or gas, which allows one to reduce the consumption of reagents, increase the sensitivity and accuracy of analysis, and shorten the time of analysis, processing, and obtaining of samples. Advances in microfluidic technologies, their advantages and potential applications, as well as prospects for the development of this field are described.

The synthesis of albumin nanoparticles was performed sequentially using the methods of pH-coacervation, desolvation and cross-linking with glutaraldehyde. The resulting particles have a shape close to spherical. A dependence of the sizes of the resulting particles on the desolvation rate was described. Immobilization of two fluorescent dyes, indocyanine green and sodium fluorescein, as well as the anti-ischemic drug quinacrine, was carried out on the surface of nanoparticles, which made it possible to obtain prolonged release forms. For quinacrine immobilized on the surface of nanoparticles, noticeable release of quinacrine ends by 30 h from the start of the experiment and accounts for 65% of the immobilized active substance. Fluorescent dyes were not released during this period.

The effect of the simulation box size on the stability of lysozyme dimers and hexamers formed in its solution before crystallization is studied by molecular dynamics. The behavior of these oligomers in boxes of different sizes is simulated, and their stability is assessed. It is shown that increasing the simulation box does not lead to refinement of the simulation results. The dimer stability weakly depends on the box sizes, while hexamers dissociated in all boxes considered, which is consistent with small-angle scattering data. The minimum distance between the protein and the box edge, at which the results of modeling oligomer behavior in crystallization solutions are reliable, is determined (1 nm).

For the first time in Russia, we present a technology for temporary wafer bonding, which is used to form through holes in silicon (through-silica via (TSV) structures) with a high aspect ratio of depth to diameter (more than 10 to 1), as well as a method for transferring alignment marks from the front to the back side of a thin Si wafer, consisting in the use of a glass carrier plate, which allows for a sufficient amount of deflection of the assembly for lithography. The modernized operating parameters of Si-glass bonding, which consist in controlling the cooling rate of the plates and applying pressure to the plates during their cooling phase, ensure a reduction in the deflection of the resulting assembly by 75% before thinning and by 65% after thinning to a residual thickness of 125 μm while maintaining the mechanical integrity of the plates.