Nanoscalic silver possesses broad-spectrum antimicrobial activities and exhibits fewer toxicological side effects than silver sulfadiazine

Silver has been used successfully for decades as an antibacterial agent and has become a standard treatment for burns and bacterial skin infections. Silver-containing creams, particularly silver sulfadiazine (SSD), possess effective activities against bacteria and fungi. However, there is serious concern that silver ions applied to denuded skin might be absorbed in significant amounts, thus introducing the risk of silver deposition, potentially leading to internal organ injury. In view of these facts we compared the percutaneous absorption and the antimicrobial potency of SSD with a new composition, nanoscalic silver (NSAg). In a murine model topical application of NSAg resulted in significantly lower percutaneous absorption and internal organ deposition compared to SSD. Strikingly, antimicrobial activity of NSAg used as a 0.1% formulation was comparable not only with 0.1% SSD against different bacterial strains including methicillin-resistant Staphylococcus aureus, but also against different yeast and dermatophyte species.From the Clinical EditorNanoscale silver (NSAg) was demonstrated to have significantly lower percutaneous absorption and less accumulation in multiple organs when applied to denuded skin. Its antimicrobial activity against MRSA was not only comparable to silver sulfadiazine, but the formulation was also effective against different yeast and dermatophyte species.

Graphical AbstractIn order to compare the percutaneous absorption of silver ions, hairless mice were treated topically for five consecutive days with either nanoscalic silver (NSAg), silver sulfadiazine (SSD), or remained untreated . After scarification, organs were prepared and further processed for ICP-MS analysis. Significantly lower concentrations of silver ions in the NSAg treated groups were detectable in liver, lung, kidney, blood, and faeces.In addition, NSAg used as a 0.1% formulation showed strong anti-bacterial activities against Methicillin-resistent Staphylococcus aureus (MRSA), Streptococcus pyogenes, Escherichia coli, and Pseudomonas aeruginosa, as well as anti-fungal activities against yeasts (Candida albicans, Candida glabrata, Malassezia sympodialis) and dermatophytes (Trichophyton rubrum, Trichophyton tonsurans, Trichophyton mentagrophytes, Microsporum canis). The observed anti-microbial activities for 0.1% NSAg were comparable with those shown for 0.1% SSD. Our results demonstrate that NSAg is a highly effective anti-microbial formulation, with a significantly lower risk for percutaneous absorption of silver ions.Figure optionsDownload high-quality image (175 K)Download as PowerPoint slide