Green synthesis of zinc and nickel dual-doped cerium oxide nanoparticles: antioxidant activity and cytotoxicity effects.

Cerium oxide nanoparticles (CeO 2 -NPs) and Zn-Ni dual-doped CeO 2 -NPs were synthesized through a green approach by the implication of zucchini peel (Cucurbita pepo) extract as a capping and reduction agent. All the synthesized samples were studied by the results of FTIR, UV-Vis, XRD, and FESEM/EDAX/PSA analyses. The Zn-Ni dual-doped CeO 2 -NPs contained a spherical morphology and their size was observed to increase at higher temperatures. The conducted MTT assay on the Huh-7 cell line displayed 50% of cells annihilation as a result of using undoped CeO 2 -NPs and Zn-Ni dual-doped CeO 2 -NPs at the inhibitory concentrations (IC 50 ) of 700 and 185.4 μg/mL, respectively. We also evaluated the enzymatic functionality of SOD and CAT of undoped CeO 2 -NPs and dual-doped NPs and found it to be dose dependent. Moreover, Zn-Ni dual-doped CeO 2 -NPs intensified the CAT activity without causing any changes in SOD activity in similar concentrations.