Effect of doping (with cobalt or nickel) and UV exposure on the antibacterial, anticancer, and ROS generation activities of zinc oxide nanoparticles

Abstract

We describe the synthesis, structural and morphological characteristics of cobalt and nickel doped zinc oxide nanoparticles (ZnO NPs) by solution combustion technique by utilizing lemon juice as bio-fuel. Structural parameters were confirmed by the X-ray Rietveld refinement method, all the compounds were crystallized in the wurtzite hexagonal structure with space group P63mc (No. 186). Field emission scanning electron microscopy coupled with energy dispersive X-ray elemental mapping results revealed agglomerated spherical shaped particles and dopant ions were homogeneously distributed. Antibacterial, anticancer, and reactive oxygen species (ROS) generation activities were studied on undoped ZnO-, Co-, and Ni-doped ZnO nanoparticles upon un-exposed/exposed to ultraviolet radiations at 300 nm for 1 h. Antibacterial studies were performed against Salmonella enterica and Clostridium perfringens. Anticancer activity was tested on HeLa and MCF-7 cell lines. Generation of ROS was studied in J744 mouse macrophage cells. Doping of cobalt or nickel in the ZnO lattice enhanced antibacterial, anticancer, and oxidative response generation activities compared to undoped ZnO NPs. These activities were further improved upon exposure to ultraviolet radiations. Together, data indicate a direct activity of ZnO NPs against bacteria, cancer cells and simultaneously boosting host’s immunity via inducing activation of immune cells (mouse macrophage cells).