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Polymer composites films based on cerium oxide nanoparticles were obtained. Xanthan gum polysaccharide was used as a matrix. The properties of the films were evaluated using optical microscopy and optical spectrophotometry. Optical microscopy shows homogenous dispersion of nanoparticles with increasing size and some agglomeration. The UV- visible spectrum of the polymer composites exhibit a red shift in the optical band gap with respect to pure xanthan and blue shift with respect to CeO2 nanoparticles. [ABSTRACT FROM AUTHOR]

Radiation is one of the factors that constantly affects living organisms. The effect of natural radiation background is supplemented by radiation from artificial radioactive sources, the most common of them are medical devices used as diagnostic and therapeutic equipment. The use of radiation therapy is based on different radiosensitivity of normal and pathologically altered organs, tissues and cells of humans and animals. The search and application of substances that change the sensitivity of living organisms to ionizing radiation to reduce the damaging effect on healthy tissues, while maintaining a positive therapeutic effect, is an urgent issue of modern medical radiobiology. Currently, nanoparticles are widely used as such substances. This paper investigates the effect of mesoporous CeO2 nanopowder on the radiosensitivity of rat alveolar and peritoneal macrophages, dermal fibroblasts, and human cervical carcinoma cells. CeO2 nanoparticles were found to have selective radiomodifying properties in relation to various types of cells. CeO2 nanoparticles had a radioprotective effect on human fibroblasts, increasing their viability after irradiation and speeding up the differentiation of fibroblasts. The nanoparticles acted as radiosensitizers on tumor cells and macrophages, enhancing the damaging effect of ionizing radiation, but the mechanism for increasing sensitivity may be different in each case. The unique enzyme-like properties of cerium dioxide nanoparticles require further investigation of the mechanisms of their action on living systems. This can give an impetus to the development of new effective methods of radiotherapy for various diseases. [ABSTRACT FROM AUTHOR]

Cerium oxide nanoparticles have recently attracted great attention as one of the promising nanomaterials for use in the pharmaceutical industry. However, to assess the potential toxicity of these nanoparticles, information about their biodistribution in the body is necessary. A physiologically based pharmacokinetic (PBPK) modeling is a convenient tool for providing such data. So, this study is devoted to modeling the pharmacokinetics of intravenously injected CeO2 nanoparticles in the body. The designed PBPK model adequately described time courses of CeO2 nanoparticles in various tissues of rats. Simulation results allow to analyze absorption, distribution, metabolism, and excretion of nanoparticles in the body, and provide important information to evaluate their toxicity to biological organisms. [ABSTRACT FROM AUTHOR]

The main problem of radiation therapy is damage to normal tissues. One of the ways to solve this problem is radiomodification using metal oxide nanoparticles. Evaluation of the effectiveness of radiomodification can be done using the dose change factor (DCF). In this paper DCF for cerium, gold and hafnium oxide nanoparticles used with monochromatic photon beams (0-300 keV) in concentration 5 mg/ml was calculated. All nanoparticles showed a significant increase of dose change factor. The results show the need to use optimal nanoparticles in radiation therapy in different energy ranges. [ABSTRACT FROM AUTHOR]

Cerium dioxide nanoparticles can be used as a photodegradable agent due to the possibility of the Ce3+ – Ce4+ transition. Activity of cerium dioxide nanoparticles can depend on many factors, such as the size and shape, their non- stoichiometry, which depend on the method of preparation and post-processing. The aim of this work was to evaluate the photocatalytic activity of cerium dioxide nanoparticles. To change the degree of stoichiometry, cerium dioxide nanoparticles were annealed at 600 °C. It was shown that annealed nanoparticles have higher photocatalytic activity compare to pure nanoparticles. [ABSTRACT FROM AUTHOR]

The 57Fe NMR spectra have been obtained in carbon encapsulated iron nanoparticles. It has been shown that the cores of the nanoparticles consist of metallic α-Fe with base-centered cubic structure, carbide θ-Fe3C, carbon-iron solid solution α-FeCX and additional phase ε-Fe2C. Quantitative phase analysis has been performed with using complex of methods. [ABSTRACT FROM AUTHOR]

New method is proposed for processing a waveform, which was not previously used to determine the voltage drop and the energy introduced into the discharge gap at the electrodes of the installation for the production of nanoparticles by spark discharge. The waveform processing method can be a useful complement to the existing techniques. [ABSTRACT FROM AUTHOR]

Nanoparticles Ag2S were synthesized by the method of chemical condensation in an aqueous solution. To assess the effect of the stabilizing agent, diluted and undiluted in alcohol MPS and various molar ratios of AgNO3 to Na2S were used. The synthesized colloidal Ag2S solutions were used to make films in several ways. The colloidal solutions and films were studied by dynamic light scattering, optical microscopy, and atomic force microscopy. The stability area of the colloidal Ag2S solution was determined. It was found that the particle size and size distribution in the films depend on the concentration of the starting reagents. The method of creating a thin film with the smallest size of Ag2S nanoparticles was developed. The self-organization of nanoparticles was discovered during the formation of a multilayer film with a diameter of particles from 0.5 to 15 µm. [ABSTRACT FROM AUTHOR]

The ion-beam synthesis of plasmonic copper nanoparticles in the matrix of optical ceramics MgAl2O4 is carried out. It was found that as a result of synthesis nonspherical metal nanostructures of the core-shell type are formed. Step annealing initiates a change in the shape of plasmon nanostructures, as well as their oxidation according to the Valency-Carter mechanism with an activation energy of 25 kJ/mol. [ABSTRACT FROM AUTHOR]