LAUSR

Zinc oxide nanoparticles (ZnO NPs) have emerged as a good anticancer and antibacterial activity, which are involved with their strong ability to trigger excess reactive oxygen species (ROS) production, release zinc ions and induce cell apoptosis. The present study aims to synthesize ZnO nanoparticles from zinc acetate (chemical co-precipitation method), and green synthesis (Sesbania grandiflora leaf extract) method evaluated their antibacterial and hemolytic activities. The prepared ZnO NPs were characterized by various techniques such as UV-visible absorption spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray analysis (EDX), high-resolution transmission electron microscope (HR-TEM) and Fourier transform infrared spectroscopy (FTIR). FE-SEM study reveals that the morphology of the crystal is spherical and flakes-shaped and the estimated sizes were 70–150 nm. The analysis of EDAX has shown the presence of zinc and oxygen. The HR-TEM analysis of zinc oxide nanoparticles with different magnifications consists of spherical shape and it is well distributed without any aggregation. The FTIR study has shown the presence of Zn–O bond, C–O bond, C–H bond, OH groups, =C–H and C=O bond. Powder XRD studies indicated the formation of pure wurtzite hexagonal structure with particle sizes of 32 and 45 nm. UV-visible spectrophotometer showed absorbance peak in range of 375–378 nm. The antibacterial activity of the ZnO nanoparticles showed antibacterial activities against both Gram-positive ( Staphylococcus aureus ) and Gram-negative ( Pseudomonas aeruginosa ) microorganisms by disc diffusion method and also determined that the cytotoxicity was assessed by hemolytic activity. Our results have revealed that zinc oxide nanoparticles could elicit hemolysis and severely impact the proliferation of lymphocytes at all investigated concentrations (25, 50, 75, 100 μg/mL). Graphical Abstract