Synthesis, Antibacterial activity, and Genotoxicity of Silver Nanoparticles

Abstract

The aim of this work was to evaluate the antibacterial activity of two types of silver nanoparticles which were prepared within a network of two hydrogels composed of Poly Vinyl Pyrrolidone PVP/Acrylamide/Acetic acid/Glycerol (Silver Nanoparticles 1 AgNP 1) and PVP/Acrylamide/Acetic acid (Silver Nanoparticles 2 AgNP2) via gamma radiation dose at 25 kGy. Furthermore, High Resolution Transmission electron microscopy (HRTEM), was used to investigate the prepared AgNPs with average size around 17.5 and 22.5 nm for AgNP1 and AgNP2 respectively. Silver Nanoparticles, antibacterial and genotoxic effects were examined on Escherichia coli ATCC 8739, Salmonella enterica ATCC 14028 and Shigella sonnei ATCC 29930 as examples for Gram negative bacteria and one Gram-positive bacteria Staphylococcus aureus ATCC 6538 as tested organisms. Silver nanoparticles (AgNP1 and AgNP2) showed strong antibacterial activity against the growth of the four bacteria tested. Gram-negative bacteria were more affected than Gram-positive bacteria. and the most sensitive was Shigella sonnei and AgNP1 was more effective than AgNP2. Effect of AgNP1 and AgNP2 on the DNA of the four bacteria was examined using 11 ISSR primers which produced 35 and 29 polymorphic bands (disappeared and new bands appeared) in E. coli, 18 and 17 polymorphic bands in Salmonella enterica and 34 and 32 in Shigella sonnei, respectively. In contrast, Gram-positive bacteria Staphylococcus aureus displayed the largest polymorphic bands numbers (38 and 49 bands) compared to Gram-negative. Additionally, all samples treated with AgNP1 or AgNP2 showed a decrease in Band Sharing Index (BSI) and Genetic Template Stability (GTS) according to ISSR profile analysis.