Study of biological activity of lanthanum, cerium, and titanium oxide’s nanoparticles and their composites modified by silver

Nanocomposites based on TiO2, CeO2 and La2O3 are characterized by adsorption, bactericidal, and virucidal properties and are used to create antibacterial coatings with disinfection air and water. At the same time, the biological activity of silver-modified nanosized particles of lanthanum, cerium and titanium oxides is promising in terms of creating the latest materials for medical and biological purposes. The paper gives a general description of the phase composition, parameters of crystal lattices, sizes of primary particles (CSR), morphology and chemical composition of nanosized structures based on cerium, lanthanum, and titanium oxides synthesized by the chemical method. The effect of nanoparticles of lanthanum, cerium and titanium oxides and their composites modified with a silver (4 wt.%) on the growth peculierities of the microorganisms belonging to different systematic and physiological groups and the implementation of different types of life strategies was studied. It has been shown that silver-modified oxide nanoparticles inhibit the activity and growth processes of almost all studied microorganisms after annual exposure at a dose of 1 mg/ml, while unmodified oxide nanoparticles can show only weak traces of bacteriostatic effect. The difference in the reaction of bacteria belonging to different systematic groups in the incubation medium of the nanoparticles under study was revealed.