Authors: B.J. Dair, K.M. Kennedy, R.S. Casas
Affilation: FDA, United States
Pages: 188 - 189
Keywords: nanoparticle, silver, antimicrobial, medical device, polymer
Silver is one of the oldest known natural antimicrobial materials, the active form being the Ag+ ion, which disrupts critical cell functions in bacteria. Reducing the size of silver particles to the nano-scale regime increases the surface area and hence the availability of silver ions, thereby enhancing their potential antimicrobial efficacy relative to their bulk counterparts. Nano-particulate silver systems have been used as anti-microbial agents for medical device applications such as bandages, wound dressings, surgical masks, endotracheal tubes, and catheters. However the surface onto which the silver nanoparticles are deposited will impact the availability of Ag+ ions due to the chemistry of the substrate surface and its affinity for silver ions. The effect of substrate material on the efficacy of nanoparticulate silver will be discussed, along with the implications of materials selection in medical device applications.