Synthesis of Stable Aqueous Ceria Sols and Study of Their Toxicity

Cerium dioxide is a unique material which is promising for biomedical applications. The properties of ceria are definitely determined by synthesis procedure and further treatment conditions. The vast majority of currently existing methods of synthesis lead to formation of CeO2 in the form of nanopowders, but in some cases (e.g., in biological applications), such powders can not be used because they do not quite satisfy practical requirements. So, in this work we succeed in synthesis of ceria-stable sols with controlled small particle size (2-4 nm) using an inexpensive and facile method and investigated the effect of changing the concentrations and the molar ratio of initial reagents on particle size of CeO2. In this paper we also propose a method of evaluation of toxicity of ceria sols using bioluminescent microorganism Vibrio fischeri. Accord-ing to the results obtained CeO2 sols of different concentrations (6.3*10-4 – 0,02M) are not toxic to Vibrio fischeri.