Synthesis and characterization of NiO nanoparticles by chemical as well as green routes and their comparisons with respect to cytotoxic effect and toxicity studies in microbial and MCF-7 cancer cell models

This contribution reports on the synthesis and also compares the main physical properties of nickel oxide nanoparticles (NiO NPs) synthesized by a completely green process using Gymnema sylvestere plant extract and sodium hydroxide as an effective reducing agent for co-precipitation method. The synthesized nanoparticles were characterized by XRD, HRTEM, EDS, FTIR, UV-visible, XPS, EPR and zeta potential analysis methods. Further the synthesized NiO NPs were evaluated the in vitro toxicity studies using microbial and MCF-7 cancer cell line models. Further cytotoxicity studies and acridine orange and ethidium bromide staining confirmed that green synthesized NiO NPs possess low toxicity compared with chemically synthesized NiO NPs.