Phyllanthus reticulatus mediated synthesis and characterization of silver nanoparticles and its antibacterial activity against gram positive and gram negative pathogens

Abstract

In this study, silver nanoparticles were successfully synthesized by using Phyllanthus reticulatus  leaf extract at different concentration (5, 10, 15 mL). The prepared samples were analyzed their optical, structural, surface morphological properties, and along with these properties, the antibacterial properties were analyzed. The UV-vis absorption spectra show SPR band around 450 nm, shift to lower wavelength due to increasing extract concentration. This shift can be ascribing to a decrease in particle size. The crystallinity nature of the prepared samples is observed by the XRD profile the calculated particles size by Scherrer’s formula displays a decrease in size with respect to leaf extract volume. From the SEM image, it can be seen that irregular and large size particles prepared at 5-10 mL and the smooth spherical shape and tiny particles were observed in the sample prepared at 15 mL. The small and spherical shape nanoparticles show good antibacterial activity against gram positive and negative bacterial pathogens. The activity of large and irregular shape particles may be due to the release of Ag+ ions and generation of ROS. Because of cell wall difference in bacteria, the better activity is observed against gram negative bacteria.