Biosynthesis of Silver Nanoparticles Using whole plant extract of the Azadirachta indica and Evaluation of Their Antimicrobial Activities

Abstract

Biomediated methods are considered to be a safer alternative to conventional physicochemical methods for the fabrication of nanomaterials due to their eco-friendly nature. In the present study, silver nanoparticles (AgNPs) were synthesized by using aqueous whole plant extract of the medicinal plant Azadirachta indica. The nanoparticles were also synthesized under ambient condition without any mechanical and chemical treatment. The silver nanoparticles were characterized by UV-vis., SEM, XRD, and TEM analysis. UV-vis. spectroscopic studies provided ample evidences for the formation of nanoparticles. The FTIR spectrum confirmed the presence of plant phytochemicals as stabilizing agent around the AgNPs. XRD and HR-TEM analyses clearly proved the crystalline nature of the nanoparticles. From the TEM images, the nanoparticles were found to be roughly spherical in shape. The AgNPs were also evaluated for their antimicrobial activity by well diffusion method against B. Subtilis, E. coli, P. aeruginosa, S. aureus, A. niger. They were found to be highly toxic against all the tested pathogenic strains.