Antioxidant effects of silver-ceria nanoparticles on the reduction of melanin in amelanotic melanoma cell biology

Although cerium oxide nanoparticles (nanoceria, CeO₂) have a wide range of applications, it is imperative to consider their significant implications for human health. In particular, modifying the surface properties of CeO₂ is of great importance in biomedical applications. In this study, a conventional wetness incipient impregnation technique was employed to load silver (Ag) metal onto the surface of CeO₂ NPs synthesized via the hydrothermal method. Then, the antioxidant effects of silver-cerium oxide nanoparticles (Ag@CeO₂ NPs) were evaluated on the melanin content of A375 skin cancer cells. The synthesized nanoparticles have been identifed using combined characterizations of the hydrodynamic size, zeta potential FTIR, FE-SEM, and UV-Vis spectra. The average particle size of Ag@CeO₂ NPs was measured at 234 ± 20 nm with the zeta potential value - 33.5 mV. FE-SEM image revealed that Ag@CeO₂ nanoparticles were polyhedral particles consisting of cubic nanostructures with rounded corners. The antioxidant capability of Ag@CeO₂ NPs was assessed using DPPH and ABTS assays and the inhibitory effects of that on melanin biosynthesis (extracellular and cellular melanin content) were examined on human melanoma cell line. Overall, the results provide promising baseline information for the potential applications of Ag@CeO₂ NPs in treating hyperpigmentation in the skin.