Silver-Impregnated Polymeric Film for Bacterial Control in Wounds

With all the concern surrounding increasing antimicrobial resistance to antibiotics, there have been concerted efforts to find other options to combatting infection in wounds. One material known for its antimicrobial properties is silver, which has been incorporated into a 20-nanometer thin polymeric film [Agarwal, A.; Weis, T.L.; Schurr, M.J.; et al. Surfaces modified with nanometer-thick silver-impregnated polymeric films that kill bacteria but support growth of mammalian cells. Biomaterials Feb 2010, 31 (4), pp. 680-690; doi:10.1016/j.biomaterials.2009.09.092].

Studies have evaluated efficacy of control and kill on Staphylococcus epidermidis to test its antimicrobial activity. High concentrations of silver have been shown to be toxic to fibroblasts and can impair wound healing. However, a very small concentration of silver nanoparticles embedded within a thin polymeric film has proven to effectively kill S. epidermidis without adverse effects on attachment or growth of mammalian cells.

Multiple polymer layers of the film form a mesh, which “melts” readily into the wound tissue to intimately conform and adhere to all irregular tissue areas of the wound. The “mesh” forms a scaffold for new cell growth while the antimicrobial action persists for three days. The film disintegrates completely in 4-5 days.

An additional application of the non-occlusive film at the next bandage change continues to exert antimicrobial effects. It is also possible to insert this silver-impregnated polymeric film subcutaneously and suture skin over the top of it.