Title: Synthesis and physicochemical properties of the nanocomposites based on sodium carboxymethyl cellulose and selenium nanoparticles

Abstract

The present study reports a simple chemical synthesis of selenium nanoparticles in the structure of the polymer and evaluates its potential biological application as an anticancer agent. Stabilized selenium nanoparticles in the solution of sodium-carboxymethylcellulose (Na-CMC) with a degree of substitution - 0.85 and degree of polymerization - 600 were synthesized. Physic-chemical properties of sodium-carboxymethylcellulose solutions contained selenium nanoparticles were studied. When selenium (IV) oxide was reduced in the presence of an aqueous solution of carboxymethylcellulose, a change in the color of the colloidal solution from yellowish orange to red was observed, which causes the formation of selenium nanoparticles. The reduction of selenium oxide SeO2 (IV) with ascorbic acid C6H8O6 in aqueous solutions of Na-CMC proceeds according to the reaction equation (1). (1) SeO2+2C6H8O6= Se0+2C6H6O6 +2H2O, which leads to the formation of zero-valence selenium Se0 (in the form of a red-orange solution) and dehydroascorbic acid which leads to the formation of zero-valence selenium Se0 and dehydroascorbic acid. It has been established that spherical monodisperse selenium nanoparticles with sizes of 2-14 nm are formed at low concentrations of SeO2. With an increasing selenium oxide concentration in Na-CMC solutions, an increase in the size of spherical nanoparticles to 4–25 nm is observed. With a further increase in the concentration of selenium oxide in Na-CMC solutions, the emerging spherical nanoparticles of selenium acquire trigonal forms and their sizes reach 4–28 nm in thickness and 12–60 nm in length. The shape and size of selenium nanoparticles in the structure of sodium carboxymethylcellulose were determined by atomic force microscopy and UV - spectroscopy methods. It was found that with increasing concentration of selenium oxide in sodium-carboxymethylcellulose solutions, as well as in films, the size and shape of selenium nanoparticles changed during the process of chemical reduction. Obtained biodegradable materials, containing selenium nanoparticles can be used in medicine as an anticancer drug for the treatment of cancer disease.