Preparing AgNPs via Biosynthesis and Chemical Reduction Techniques and Evaluating Their Antibacterial Effects

Abstract

Silver nanoparticles (AgNPs) is one the most important metal in medical aspect specially as antibiotics. AgNPs show very interesting antimicrobial properties, even when used at low concentrations. Also, these cost-efficient materials have negligible immunological responses and cytotoxicity. In this study evaluation chemical reduction and biosynthesis methods of Synthesis of silver nanoparticles and this affect on antibacterial application. For this reason we prepared both of chemical nano particles and biosynthesied nanoparticles of silver and evaluated the antibacterial effects on Both of gram negative and gram positive bacteria. Size, morphology and composition of NPs were studied by scanning electron microscopy (SEM), laser particle analyzer (LPA) and ultraviolet-visible spectroscopy (UV-Vis). Our results showed that UV-Vis spectroscopy was performed to represent AgNP suspensions’ plasmon bands. The results show a sharp absorbance peak for AgNPs at 430 nm. For the biological synthesis of AgNPs, the preparation process was monitored through the color variations. Afterward, UV-Vis spectrophotometry was performed to measure its optical parameters. The results revealed an absorbance peak at 420 nm for the AgNPs. AgNPs produced by biological and chemical reduction methods were tested for their antimicrobial activity. To this end, Gram-negative and Gram-positive bacteria were taken using the Agar well diffusion technique. presents the diameter of inhibition zones around each well with chemically prepared AgNPs, biologically synthesized AgNPs, and AgNO3. The highest antibacterial activity of NPs was observed in E. coli, which was more than that of S. aureus. In addition, the biosynthesized NPs showed higher antibacterial activity than those prepared using the chemical method. Finally as conclusion The results  of our study showed that producing NPs by the biosynthesis technique was more powerful than chemical processes, and the produced NPs offer a higher antibacterial activity against s,arouse.