Synthesis of cerium-oxide NPs and their surface morphology effect on biological activities

Herein, reliable work has been carried out on the synthesis of cerium-oxide (CeO₂ ) nanoparticles (NPs) via hydrothermal and co-precipitation methods. We emphasize the highly adequate hydrothermal method for synthesizing CeO₂ NPs for biomedical applications. Absorption spectra showed peaks at 283 and 274 nm, which confirm the formation of CeO₂ NPs for hydrothermal (HYNPs) and co-precipitation (CONPs) methods, respectively. Functional group analysis firmly showed the presence of organic and inorganic species, which revealed similar characteristics of both HYNPs and CONPs. The cubic structure and the average crystallite size of the synthesized NPs are determined using Scherrer's and Williamson–Hall methods. The obtained average particle size is compared by using high-resolution transmission electron microscopy, which is around 10 and 5 nm for HYNPs and CONPs, respectively. Further, we studied their antimicrobial activities and consequently, the synthesized CeO₂ NPs showed excellent antimicrobial activities. Moreover, HYNPs yielded promising antioxidant activity with the lowest IC 50 as compared with CONPs. Owing to the biological activity of CeO₂ NPs, HYNPs act as best therapeutic agents in biomedical applications as well as its vital role in antibiotics. (author)