Nanoporous Layers and the Peculiarities of Their Local Formation on a Silicon Wafer

This review presents the results of the local formation of nanostructured porous silicon (NPSi) on the surface of silicon wafers by anodic etching using a durite intermediate ring. The morphological and crystallographic features of NPSi structures formed on n- and p-type silicon with low and relatively high resistivity have also been investigated. The proposed scheme allows one to experiment with biological objects (for example, stem cells, neurons, and other objects) in a locally formed porous structure located in close proximity to the electronic periphery of sensor devices on a silicon wafer.

CLARITY and Light-Sheet microscopy sample preparation in application to human cerebral organoids

Cerebral organoids are three-dimensional cell-culture systems that represent a unique experimental model reconstructing early events of human neurogenesis in vitro in health and various pathologies. The most commonly used approach to studying the morphological parameters of organoids is immunohistochemical analysis; therefore, the three-dimensional cytoarchitecture of organoids, such as neural networks or asymmetric internal organization, is difficult to reconstruct using routine approaches. Immunohistochemical analysis of biological objects is a universal method in biological research. One of the key stages of this method is the production of cryo- or paraffin serial sections of samples, which is a very laborious and time-consuming process. In addition, slices represent only a tiny part of the object under study; three-dimensional reconstruction from the obtained serial images is an extremely complex process and often requires expensive special programs for image processing. Unfortunately, staining and microscopic examination of samples are difficult due to their low permeability and a high level of autofluorescence. Tissue cleaning technologies combined with Light-Sheet microscopy allows these challenges to be overcome. CLARITY is one of the tissue preparation techniques that makes it possible to obtain opaque biological objects transparent while maintaining the integrity of their internal structures. This method is based on a special sample preparation, during which lipids are removed from cells and replaced with hydrogel compounds such as acrylamide, while proteins and nucleic acids remain intact. CLARITY provides researchers with a unique opportunity to study three-dimensional biological structures while preserving their internal organization, including whole animals or embryos, individual organs and artificially grown organoids, in particular cerebral organoids. This protocol summarizes an optimization of CLARITY conditions for human brain organoids and the preparation of Light-Sheet microscopy samples.

The influence of Gd-DOTA ratios conjugating PLGA-PEG micelles encapsulated IR-1061 in bimodal over–1000 nm near–infrared fluorescence and magnetic resonance imaging

Multimodal imaging can provide multidimensional information for understanding concealed microstructures or bioprocesses in biological objects. The combination of over–1000 nm near–infrared (OTN–NIR) fluorescence imaging and magnetic resonance (MR) imaging is...

Storage of Imidaclopride and Acetamyprid in Biological Objects and Study of Conservative Effects on This Process

In this article is studied the biological conditions of imidacloprid and acetamiprid pesticides under laboratory conditions and the storage of the objects in a state preserved in ethyl alcohol. There were determined in the composition of the biological object stored in the laboratory the imidacloprid was detected after 13.07% in 90 days and in objects preserved with ethyl alcohol - 14.05%. When the biological object containing acetamiprid was analyzed after 90 days, it was found to be 4.45%, and when the object was stored under 95% ethyl alcohol5.72%. In the analysis of acute poisoning cases with imidacloprid and acetamiprid, it is recommended that their shelf life should be taken into consideration.

Study of the effects of ultra-low intensity electromagnetic fields on biological objects

The object of research is the efficiency of exposure to electromagnetic field (EMF) of ultra-low intensity on biological objects, which is formed by a generator of broadband radiation. The principle of action of the generator is based on formation of electromagnetic radiation induced by periodic pulsed gas discharge in coaxial system of electrodes, which is loaded on a dielectric rod antenna. The method of selection of signals and corresponding equipment, which energy characteristics of radiation correspond to the criterion of non-thermal influence on bioobjects, is developed for obtaining a comparative assessment of influence bioefficiency. The proposed new method for processing experimental data using statistical calculations that meet the requirements for the processing and interpretation of the results. The seeds of wheat and interaction of millimeter range electromagnetic oscillations with bone marrow cells of rats were used as biological objects for investigating the effect of millimeter range electromagnetic oscillations. A biosensory effect was obtained when exposed to broadband radiation of ultra-low intensity, compared to the control sample. A change in the properties of the seeds, in particular, heat resistance, is observed. According to the experimental data, seeds turn out to be less susceptible to heat as a result of their pretreatment with EMF. The biological response is observed to depend on the frequency and time of irradiation. Also, the dependence of the decrease in the number of dead cells on the time of EMF irradiation was experimentally proved. The equation of dependence of selective average proportion of dead cells in rat bone marrow on irradiation time was calculated. Biosensory effect of exposure to broadband ultra-low intensity EMF of the developed emitter was revealed. It was established and statistically proved that the minimum time with the maximum positive effect of exposure to electromagnetic radiation of millimeter range on bone marrow cells of rats is 30 minutes, compared with an unirradiated sample. The results make it possible to evaluate the positive effect of electromagnetic oscillations on biological objects and propose the results of studies for practical use in the development of medical systems.

Innovative research carried out at the nanocenter of the NRC “Kurchatov Institute” – CRISM “Prometey”

This article presents the results of comprehensive innovative research carried out over the past 15 years at the Nanocenter of the NRC “Kurchatov Institute” – CRISM “Prometey” in the following areas: the creation of coatings based on quasicrystals of the Al-Cu-Fe system, laser synthesis technologies, systems electromagnetic protection of technical equipment and biological objects, structural ceramics and composite materials, technologies for surface modification and magnetron sputtering, obtaining powders by melt spraying, hydrogen and alternative energy.

Mathematical modeling of equivalent ellipse radii of Raman spectra for identification of gold nanoparticles

To ensure the biomedical, therapeutic and protective properties of textile materials using gold nanoparticles, there is a need to apply the convergence of nano-, bio-, info -, cognitive sciences and technology. It is proposed to evaluate the accuracy of identification of colloidal gold nanoparticles on organic fibers based on the multidimensional correlation components of the Raman spectra under control by the polarization characteristics. The aim of the work is to improve the accuracy of identification of gold nanoparticles in nanostructured biological objects during mathematical modeling based on the components of Raman spectrograms.The paper analyzes the Raman spectra of polyester fibers with and without gold nanoparticles in different ranges. A method for solving a system of multidimensional equations with differentiation in X and Y is proposed, according to which the coordinates of the intersection points of ellipses are determined under conditions of equality of equivalent radii and probability densities of two-dimensional distributions. The sensitivity to the concentration of gold nanoparticles of the developed method under various conditions is estimated. The research carried out in this work will improve the accuracy of identification of gold nanoparticles on various biological objects, as well as solve a wide range of problems related to increasing the reliability of control of metal nanoparticles

The calculation of the field of an antenna located near the human head

In this work, a numerical calculation was carried out in one of the universal programs for automatic electro-dynamic design. The calculation is aimed at obtaining numerical values for specific absorbed power (SAR). It is the SAR value that can be used to determine the effect of the antenna of a wireless device on biological objects; the dipole parameters will be selected for GSM1800. Investigation of the influence of distance to a cell phone on radiation shows that absorbed in the head of a person the effect of electromagnetic radiation on the brain decreases by three times this is a very important result the SAR value has decreased by almost three times it is acceptable results.