Electrically modified lyophilic silver hydrosol inhibits bacterial growth in a dose-dependent manner in vitro and in vivo

Abstract

Silver has been known for many medicinal uses in the forms of colloidal silver and silver nanoparticles, both of which pose possible health risks when improperly applied. Silver in the form of an electrically modified hydrosol bypasses the adverse effects of prior forms, yet still maintains potent antimicrobial properties. This study focuses on the efficacy of this electrically modified silver hydrosol against Alcaligenes faecalis, Escherichia coli, Methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Staphylococcus epidermidis in an in vitro concentration-dependent manner and an in vivo dose-dependent manner. The in vitro concentration-dependent test is a modified Kirby-Bauer disk diffusion method to measure the zone of inhibition (ZOI). The in vivo dose-dependent test measures percent decrease on live epithelial tissue. The concentration-dependent test results found statistically significant ZOI (all p < 0.01), yet all but S. epidermidis treatments failed post-hoc test significance. The dose-dependent test yielded a near-total eradication of cultured bacteria, up to a 100% decrease in bacterial growth (p ≤ 0.0463), with no change between treated and untreated epithelial cells. These results suggest safe usage of the silver hydrosol in vivo and support the hypothesis of high-efficacy dose-dependent treatment on multiple nosocomial gram negative and gram positive bacterial strains. Future research could focus on silver hydrosol's interaction within a living system with exhaustive testing on the effects on endogenous microflora and hepatocytes for presence of silver oxide.