In Ukrainian

Abstract

The prevalence of Cerium compounds, economic affordability, and unique redox properties determine the wide range of cerium oxide applications. The transition to nanosized particles of cerium oxide allows these materials to reversibly absorb and release oxygen, which determined the use of nano-CeO2 in biomedical technologies in the treatment of diseases associated with lesions due to oxidative stress. The review analyzed the state of modern scientific literature regarding the properties, methods for producing and using cerium nanooxide. The main characteristics of cerium oxide and the features of its structure are described, the mechanisms of action of the enzyme-like properties of nanoceria are given. It was shown that the coexistence of Ce3+ and Ce4+ ions on the surface is compensated by the formation of oxygen vacancies, which are essentially surface defects. Their number depends on the particle size, morphology and crystallinity of the material. These surface defects are catalytic centers that are capable of exhibiting the enzyme-like properties of nanoceria and effectively absorbing free radicals, which include reactive oxygen species. Physicochemical properties of nanoparticles depend on the synthesis parameters. These include the nature and type of precursor, stabilizing agent and solvent, the duration and temperature of the reaction, and the pH of the reactive mixture. So, microgravity affects morphology, average particle size, crystallinity; an increase in the aging time leads to the synthesis of large particles and crystallites, increases the degree of crystallinity. The synthesis temperature affects the size and structure of crystallites, agglomeration, surface defects and oxidation state. Varying the synthesis parameters and their control during the reaction allows one to obtain particles with desired physicochemical properties. The main methods are analyzed in detail: deposition, hydrothermal, microemulsion, combustion, sol-gel and green. It has been established that, due to its unique properties, nanosized cerium oxide has a wide range of applications. It is used as an abrasive powder for polishing glass and protecting it from corrosion; commercial sunscreens are produced on its basis, biosensors and solid oxide fuel cells are constructed, and catalysts are synthesized. Cerium oxide nanoparticles and materials based on it are widely used in environmental, industrial, bioanalytical and biomedical fields. Recently, the biomedical use of nanosized cerium oxide has been rapidly developing. The non-stoichiometric composition of cerium oxide nanoparticles allows it to effectively neutralize reactive oxygen species while protecting the body from oxidative stress. Nano-CeO2 is used in the treatment of inflammatory, cardiovascular and neurodegenerative diseases, it increases the activity of antimicrobials, is an agent for the delivery of therapeutic drugs to cancer cells.