Evaluation of biological potential of UV-spectrophotometric, SEM, FTIR, and EDS observed Punica granatum and Plectranthus rugosus extract-coated silver nanoparticles: A comparative study

Recent developments in the green synthesis of metallic nanoparticles (NPs) using phytoconstituents have attracted the attention of the global scientific community. The present study was designed to synthesize silver NPs (AgNPs) using Punica granatum and Plectranthus rugosus plant extracts. The fabricated AgNPs were characterized using UV-visible spectrophotometry (UV-Vis), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive x-ray spectroscopy (EDS). The shift in the color of the silver nitrate (AgNO3) solution after the addition of P. granatum and P. rugosus extracts indicated the synthesis of AgNPs. The effect of AgNO3 concentrations and pH on the synthesis of AgNPs was also evaluated. The findings of this study suggest that AgNO3 concentration of 1 mM, reaction time of 1 h, and pH of 7 at room temperature were the best suited conditions for the synthesis of AgNPs. According to the FTIR analysis, amidic and carbonyl compounds were primarily responsible for the encapsulation of AgNPs. SEM investigations have shown irregularly shaped geometry with sizes of 35 nm (P. granatum) and 33 nm (P. rugosus) with low agglomeration. The prepared AgNPs exhibited good potential for 2,2-diphenyl-1-picrylhydrazyl radical scavenging, with values of 70% (P. granatum) and 68% (P. rugosus). Hence, we conclude that the leaves of P. granatum and P. rugosus are excellent material for designing of different plant-extracted-conjugated AgNPs for biomedical applications.