Green synthesis of selenium nanoparticles using Delonix regia and Nerium oleander flower extract and evaluation of their antioxidant and antibacterial activities

Abstract

Bionanotechnology has emerged up as integration between biotechnology and nanotechnology for developing biosynthetic and environmental friendly technology for synthesis of nanomaterials. Delonix regia and Nerium oleander flower extract-mediated synthesis of selenium nanoparticles (SeNPs) were carried out under room temperature and the results are reported in the present study. The synthesized SeNPs were characterized by the primary analytical techniques like UV–Visible spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX) spectroscopy and atomic force microscopy. All the characterization techniques revealed that the phytochemicals present in the flower extracts not only assisted the formation of hexagonal crystalline SeNPs by capping, but also stabilized the formed nanoparticles. The synthesized SeNPs exhibited a considerable antibacterial activity against Escherichia coli, Pseudomonas aeruginos, and Aeromonas hydrophila. The tentative mechanism of antibacterial activity is also proposed. The synthesized SeNPs also exhibited a greater antioxidant activity than the standard as revealed by hydrogen peroxide assay.