Cerium oxide nanoparticles: green synthesis using Banana peel, cytotoxic effect, UV protection and their photocatalytic activity.

Nanomaterials, as an active ingredient, have been widely deployed in various science and technological applications with zinc and titanium oxides nanoparticles being commonly applied in sunscreens. On similar lines, cerium oxide nanoparticles (CeO-NPs) were synthesized using Musa sapientum peel extract, to investigate its cytotoxic effects, UV protection and photocatalytic activity. The synthesized nanoparticles were identified through Raman, Powder X-ray Diffraction (PXRD), Fourier-Transform Infrared spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM) and Energy-Dispersive Spectroscopy (EDX). FESEM results showed that the size of synthesized nanoparticles is in the range 4-13 nm. Their cytotoxic activity revealed a non-toxic behavior in concentrations below 500 μg/mL on lung (A549) cell lines. The Sun protection factor (SPF) was estimated approximately ~ 40 for synthesized CeO-NPs. The survey of photocatalytic activity showed that synthesized nanoparticles can remove 81.7% of AO7 in 180 min under visible light.