Chemical and Physical Analyses of Synthesized Silver Nanoparticles

Although silver has long been used as an antimicrobial agent, it is not used often due to economical and environmental concerns. However, silver nanoparticles (AgNPs) have the same properties as elemental silver and can be synthesized on a considerably more economical level. The objective of this study was to synthesize AgNPs and analyze their physical, chemical, and antimicrobial properties. The first portion of this study consisted of synthesizing AgNPs of 5nm, 35nm, 40nm, and 60nm lengths, using diluted lab solutions and sterile techniques. The physical analysis of the AgNPs was performed through visual color comparisons of their varied sizes, which confirmed their successful synthesis. A chemical analysis was then conducted using ultraviolet-visible spectroscopy, which measured their absorbance at a 635nm wavelength. Finally, the antimicrobial property of the AgNPs was investigated by inoculating a strain of Staphylococcus aureus with titrated concentrations of varied nanoparticle size. This titration allowed for the analysis of the relationship between the size of AgNPs and level of inhibition of S. aureus. The results of the bacterial inhibition were quantified using a colorimeter, which determined the density of the bacteria and the consequent level of inhibition. The results were analyzed using an ANOVA test, which determined that at a 95% significance level, AgNPs were successfully able to inhibit the growth of S. aureus. However, the results of an ensuing series of t-tests indicated that there was not a consistent relationship between the size of the nanoparticles and the level of bacterial inhibition