Antimicrobial activity of electrochemical silver ions in nonionic surfactant solutions and in model dispersions

The microbicidal effectiveness against Gram-positive and Gram-negative bacteria and Candida albicans of electrochemical silver ions in aqueous solutions containing nonionic surfactants was investigated. From the perspective of the possible use of anodic silver as a preservative in cosmetic or pharmaceutical preparations, microbicidal efficacy was also studied in oil/water model dispersions. Surfactants and botanical extracts partially inhibited the microbicidal effectiveness of anodic silver. Nevertheless in all the experimental conditions, silver ions reduced the microbial concentration up to 4 log units of the starting inoculum in less than 6 h. The wide microbicidal spectrum and the high rate of kill of silver ions appear, therefore, attractive enough to suggest a possible utilization of anodic silver as a preserving agent.