Synthesis and Characterization of Gold ‎Nanoparticles using Plant Extract of ‎Terminalia arjuna with Antibacterial ‎Activity

   The use of plant extracts for nanoparticles synthesis are green, economical and cost effective approach.  The present study reports the bio-synthesis of gold nanoparticles (Au NPs) using leaf extract of Terminalia arjuna. After exposing the gold ions to aqueous solution of leaf extract, rapid reduction of gold ions into gold nanoparticles is observed within few minutes. The characterization of biosynthesized Au NPs were carried out by ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX) techniques. UV-visible spectrum of the aqueous medium containing gold nanoparticles showed a peak of 530 nm. TEM analysis was performed to examine the size and shape of the biosynthesized gold nanoparticles. TEM analysis indicated that gold nanoparticles were well dispersed and ranged between 15 to 30 nm in size. Antibacterial activity of the biosynthesized Au NPs was studied against common human pathogens such as Staphylococcus aureus (NCIM 5021), Pseudomonas aeruginosa (NCIM 5029), and Salmonella typhimurium (NCIM 2501) by agar well diffusion method. This method exploits the economical and greener approach for the synthesis of metallic nanoparticles.