Antibacterial and Cytotoxic Effects of Silver Nanoparticles on Staphylococcus aureus and Normal Vero Cells

Abstract

Silver nanoparticles (AgNPs) are of special concern as a result of their unique chemical, physical and biological characteristics. It has become an attractive alternative to antibiotics due to their broad-spectrum antimicrobial activity.The study aimed to determine the antibacterial activity of AgNPs against S. aureus bacteria and the effect of AgNPs on the viability of normal cell line (vero cell). A total of 70 clinical samples (wound and vagina swab, stool and urine) were used in this study. Bacterial isolates were subjected to the microscopical, cultural and biochemical evaluation.AgNPs were prepared and checked for their antimicrobial activity by the use of various concentrations employing agar dilution method. In addition, the effect of different concentrations of AgNps on a viability of vero cells was examined. The results showed that out of 70 clinical samples, 11 (15.7%) isolates were Staphylococcus aureus.AgNps showed high activity against S. aureus at concentrations (100 μg/ml and 200μg/ml). It was found that there was no effect of AgNPs on the viability of the normal vero cells at (≤ 250 μg/ml) concentration, but they have cytotoxic effect on the viability of the these cells at high concentrations. This study concluded that AgNPs possess good antimicrobial activity and the concentrations that maintain the cell viability could be used as an alternative therapy to treat S. aureus infections.