Coating of cerium oxide nanoparticles with different carbohydrates

Abstract

Cerium oxide nanoparticles (nCeO2) are biomaterials with numerous applications in biomedicine, fuel additives and electronics. Since their low stability in aqueous media limited their practical application, the aim of this study was to improve the suspension stability of nCeO2 by coating the particles. Glucose, monosaccharide, and levan and pullulan, microbial polysaccharides, were used as coating material. The coating was attempted under different synthesis conditions, by adding the carbohydrates during (direct coating) or after (subsequent coating) the synthesis of nCeO2. X-Ray diffraction analysis, Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for characterization of nanoparticles’ powders. Measuring of hydrodynamic size, zeta potential and turbidity was used for the estimation of nanoparticles’ suspension stability in aqueous media. The success of subsequent coating with carbohydrates and the differences between coated nCeO2 have been proven with FT-IR spectra. Turbidity measurement showed the best stability of levan- and glucose-coated nCeO2 suspensions. It can be concluded that coating with carbohydrates improved the stability of the nCeO2 suspension by decreasing the size of aggregated particles. The obtained results open new horizons for further ecotoxicity investigation and nCeO2 application.