OICC Press Journal of Nanostructure in Chemistry 2193-8865 3 1 (December 2013) 2013 08 05 Phytosynthesis of silver nanoparticles using Pterocarpus santalinus leaf extract and their antibacterial properties 10.1186/2193-8865-3-68 EN Kasi Gopinath Department of Nanoscience and Technology, Alagappa University, Karaikudi, Tamil Nadu, 630 004, IN Shanmugam Gowri Department of Nanoscience and Technology, Alagappa University, Karaikudi, Tamil Nadu, 630 004, IN Ayyakannu Arumugam Department of Nanoscience and Technology, Alagappa University, Karaikudi, Tamil Nadu, 630 004, IN Journal Article 2013 08 05 Abstract Green synthesis is one of the rapid, reliable, and best routes for the synthesis of silver nanoparticles (Ag NPs). The current study revealed that the aqueous leaf extract of Pterocarpus santalinus , which contains steroids, saponins, tannins, phenols, triterpenoids, flavonoids, glycosides, and glycerides, is found to be responsible for bioreduction during the synthesis of spherical Ag nanoparticles. The formed Ag NPs were characterized by ultraviolet-visible (UV-vis), Fourier transform-infrared (FT-IR), X-ray diffraction (XRD), atomic force microscopy (AFM), energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM) analysis. UV-vis spectra of the aqueous medium containing silver nanoparticles showed a surface plasmon resonance peak at 418 nm. FT-IR analysis was performed to analyze the biomolecules responsible for the reduction of Ag NPs. XRD results confirmed the presence of silver nanoparticles with face-centered cubic structure. The EDX analysis showed the completed inorganic composition of the synthesized Ag NPs. AFM analysis exemplified the results of particle sizes (41 nm). The calculated crystallite sizes are in the range of 20 to 50 nm, and the spherical nature of the Ag NPs was ascertained by SEM. The synthesized Ag NPs exhibited good antibacterial potential against gram-positive and gram-negative bacterial strains. The zone of inhibition effect of antibacterial activity depends upon the concentration of Ag NPs.