Phytofabrication of Nickel and Cobalt–Nickel Nanoparticles Using <i>Acacia concinna</i> Pod Extract and Evaluation of its Anticancer Activity

Abstract In this study, we investigated the phytofabrication of nickel (Ni) and cobalt–nickel (Co–Ni) nanoparticles (NPs) with Acacia concinna pod extract. The biosynthesized nanoparticles were studied using various spectral techniques. The anticancer activity of the extract and the biosynthesized nanoparticles was evaluated using an MTT (3‐(4, 5‐dimethylthiazolyl‐2)‐2, 5‐diphenyltetrazolium bromide) assay. UV–visible spectroscopy revealed that the surface plasmon resonance (SPR) bands of Ni and Co–Ni NPs were found to be at 293 and 291 nm, respectively. Fourier transform infrared spectroscopy (FTIR) analysis of the extract reveals the presence of phytochemicals and nanoparticles. The amorphous nature of the synthesized metallic nanoparticles was identified through X‐ray diffraction (XRD) analysis. Scanning electron microscopy (SEM) and field emission scanning electron microscopy (FESEM) analysis show that the synthesized nanoparticles are in an aggregated form. The pod extract and synthesized nanoparticles exhibit cytotoxic activity, with cobalt–nickel nanoparticles demonstrating the highest cytotoxicity against A549, HeLa, HepG2, and MCF‐7 cells. This study demonstrates that the phytofabrication of nickel and cobalt–nickel nanoparticles using the pod extract of A. concinna shows promising anticancer activity.