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Reactive oxygen species (ROS) involving superoxide anion, hydrogen peroxide and hydroxyl radical play important role in human health. ROS are known to be the markers of oxidative stress associated with different pathologies including neurodegenerative and cardiovascular diseases, as well as cancer. Accordingly, ROS level detection in biological systems is an essential problem for biomedical and analytical research. Electrochemical methods seem to have promising prospects in ROS determination due to their high sensitivity, rapidity, and simple equipment. This review demonstrates application of modern electrochemical sensors for ROS detection in biological objects (e.g., cell lines and body fluids) over a decade between 2011 and 2021. Particular attention is paid to sensors materials and various types of modifiers for ROS selective detection. Moreover, the sensors comparative characteristics, their main advantages, disadvantages and their possibilities and limitations are discussed. [ABSTRACT FROM AUTHOR]

The paper proposes an overview of the primary applications of generalized two-dimensional correlation spectroscopy (2D-COS) to analytical chemistry. 2D-COS is a method used to analyze datasets obtained by spectroscopic measurements. This approach is based on the use of 2D correlation maps to detect and analyze correlations between different spectral regions or data from two measurement methods. The objective of employing 2D-COS is to enhance the volume of analytical information by uncovering latent correlations within the data. Analysis of such correlations for series of spectral data, acquired over a range of analyte concentrations, pH values, or component ratios in mixtures, and also under varying temperatures or other external factors, enables investigating and elucidating chemical processes and interactions. This information is not readily attainable directly from the spectra. In comparison to one-dimensional spectra, 2D-COS excels in the significance of analytical information, particularly in the identification of components and the determination of the composition of complex mixtures. 2D-COS can also be used for monitoring changes in a sample over time, which makes it a valuable tool for studying dynamically evolving systems. Overall, 2D-COS is a sufficiently versatile approach that can be employed in conjunction with numerous methods, addressing a wide range of analytical tasks and complex samples, also without sample preparation. The review highlights achievements in the application of 2D-COS by the beginning of September 2023. [ABSTRACT FROM AUTHOR]

Information about the sources and mechanisms of plutonium release into the environment is summarized. The magnitudes and distribution of global plutonium fallout, as well as data on technogenic sources of plutonium isotope releases into the environment, are reviewed. For this purpose, the supply of plutonium as a result of nuclear explosions at test sites, such as Nevada, Semipalatinsk, Novaya Zemlya, etc., and the scale of environmental contamination as a result of tests were considered. The data on the intake of plutonium after nuclear and radiation accidents at nuclear power plants (Chernobyl nuclear power plant, Fukushima, etc.) and at enterprises of the nuclear complex (Kyshtym accident, etc.) are presented. Separately, plutonium intake into the natural environment through emissions and discharges of nuclear complex enterprises (Sellafield, MCC (Krasnoyarsk), etc.) is considered. Information about the levels and content of plutonium isotopes in various media and environmental objects, as well as information about the parameters characterizing the migration of plutonium in various media and the transition between them is generalized and presented. Forms of plutonium occurrence in soils (distribution by granulometric fractions, chemical forms, "hot" particles, etc.) are considered, and information on the characteristic levels of plutonium concentrations in soils for various objects is summarized. Data on the concentrations of plutonium in the air are given. Information on the forms of plutonium in the aquatic environment, as well as on the characteristic levels of plutonium concentrations in various water bodies, including the World's oceans, is presented. Information on the transition coefficients of plutonium isotopes in the soil–plant system is summarized. Particular attention is paid to plutonium isotopes in biological objects and the human body. [ABSTRACT FROM AUTHOR]

Based on low-temperature SQUID sensors, an ultra-sensitive magnetometric system has been created for the analysis of nanoparticles in biological objects. The main features of the SQUID magnetometric system and information technology during registration and analysis of magnetic signals from organs of laboratory animals are considered. Experimental data on the operation of the magnetometric system and algorithms of data recording and processing in the study of physical models (small animals) with nanoparticles are presented. [ABSTRACT FROM AUTHOR]

In the present article a spatial confinement of microobjects were explored in the radiofrequency Paul trap at normal pressure. Spores of Lycopodium Clavatum, 33 μm in diameter, and CdSe/ZnS (core/shell) quantum dots conglomerates with size of 2–7 μm were used as such microobjects. Zero-crossing orbits of these objects were observed for the first time what indicates the nonlinear nature of dynamics of these particles in localization area. Mathematical description of particle dynamics in a viscous is presented. It is shown that friction value depends on the radius of microobjects and dynamic viscosity. Moreover, zero-crossing orbits of charged particles in the radiofrequency Paul trap were numerically simulated. A new method of comparative analysis of the morphology of microparticles is proposed. [ABSTRACT FROM AUTHOR]

The aim of the work was to develop electronic database of biological organisms (fishes, viruses) on the base of the methods that have been used before in mathematics, engineering, physics. The methods of object-oriented system analysis, construction of models of subject spaces (problem space, solution space), ER-diagrams, of constructing databases and others were applied. The examples of prototypes of modern databases with information about fishes developed over the past years in Western European and American countries were presented. An overview of applied methods, concepts and terminology from the areas of object-oriented system analysis, database designing was disclosed. In conclusions the description of constructed database and practical recommendations for the development of databases with the information about domestic biological organisms for electronic information systems are given. [ABSTRACT FROM AUTHOR]

A device was developed for searching of optimal parameters for the treatment of biological objects by an alternating magnetic field, where the optimal parameters are determined through automated analysis of the dependencies of the physical characteristics of biological liquids obtained from those biological objects on the frequency and strength of the field. [ABSTRACT FROM AUTHOR]

Cavitation, which yet has not found a wide application in industrial technologies, is an effective method of hydro-mechanical intensification of chemical-engineering, food, pharmaceutical, biological and other processes. The effectiveness of cavitation process is enabled by cavitation crashing of the solid phase, turbulent diffusion of boundary layer of the fluid by cavitation bubbles, emergence mass transfer aspects, which are characterized by high values of mass transfer coefficients. Processing of biological objects in a cavitation field can be used as an independent process and ensure an inactivation and extinction of microorganisms or as cyanobacteria pretreatment stage with the aim of increasing the mass transfer surface for the following extraction or biochemical processes. The results of microscopic analysis showed that for certain modes of processing of liquid substances in the cavitation field the decrease of contrast cells is observed as well as damage to the cell membrane, reducing the clarity of contours, cell shape change, aggregation and mechanical damage. Experimental studies have established that in the case of hydrodynamic cavitation to increase the effectiveness of the process of obtaining energy from cyanobacterial biomass, treated in a hydrodynamic cavitation field cyanobacterial biomass, a degree of lipid extraction is increased by 54,3 % and the number of synthesized biogas increases by 28,3 %. [ABSTRACT FROM AUTHOR]

Two methods have been developed for determining antitumor drug vinblastine in blood plasma and prostate gland tissue by high performance liquid chromatography ( HPLC) and capillary electrophoresis ( CE) with detection at 214 nm. The lower limit of quantitative determination (15 ng/mL) was achieved with HPLC. The higher accuracy ( CV), precision and selectivity have been achieved with CE method, 0.09, 90, and 100%, respectively. The sample preparation of blood plasma and previously homogenized prostate gland tissue included solid-phase extraction on Supelco DSC-18 cartridges. The recovery of vinblastine from the blood plasma was 91 ± 3% and from the tissue, 82 ± 5% ( n = 6). The developed methods were implemented for the therapeutic monitoring of vinblastine in the procedure of intracavitary drug electrophoresis. [ABSTRACT FROM AUTHOR]

We have analyzed the feasibility and expediency of using a probabilistic neural network as a classifier for processing and interpreting data obtained using a biosensor we have developed that is based on whispering-gallery-mode optical resonance. We have established that the probabilistic neural network makes it possible to correctly classify the biological compounds under study with average 97.3% probability. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we summarise the development of off-axis electron holography on biological samples starting in 1986 with the first results on ferritin from the group of Tonomura. In the middle of the 1990s strong interest was evoked, but then stagnation took place because the results obtained at that stage did not reach the contrast and the resolution achieved by conventional electron microscopy. To date, there exist only a few (∼12) publications on electron holography of biological objects, thus this topic is quite small and concise. The reason for this could be that holography is mostly established in materials science by physicists. Therefore, applications for off-axis holography were powerfully pushed forward in the area of imaging, e.g. electric or magnetic micro- and nanofields. Unstained biological systems investigated by means of off-axis electron holography up to now are ferritin, tobacco mosaic virus, a bacterial flagellum, T5 bacteriophage virus, hexagonal packed intermediate layer of bacteria and the Semliki Forest virus. New results of the authors on collagen fibres and surface layer of bacteria, the so-called S-layer 2D crystal lattice are presented in this review. For the sake of completeness, we will shortly discuss in-line holography of biological samples and off-axis holography of materials related to biological systems, such as biomaterial composites or magnetotactic bacteria. [Copyright &y& Elsevier]

Biological objects were micromanipulated with a magnetic microactuator. These objects are pushed with a small ferromagnetic particle whose size can be as small as 10 × 10 × 5 μm[sup 3] . This particle is called the manipulator and is moved thanks to a permanent magnet. This magnetic device allows the manipulation of objects in an extremely confined space. As biological objects are fragile, the force applied on them must be controlled during the manipulation. The model we present allows to determine the force applied by the device on the manipulated object. Several experimental measurements are presented in order to validate the model. [ABSTRACT FROM AUTHOR]