Challenging Silver – Influence of Extraction Medium on the Release of Silver from a Wide Range of Commercial Silver Dressings

A number of antimicrobial silver dressings based on different substrates and silver technologies have been introduced recently. Initial in vitro testing of a new cost-effective silver dressing* showed a strong dependence between silver release and the ionic strength and organic content of the extraction solution. To answer the question if all silver dressings show similar dependence on extraction medium, a number of commercial dressings were tested using simulated wound fluid (SWF =142mM sodium chloride and 2.5mM calcium chloride in water) and SWF plus 5% bovine serum albumin (BSA) as the extraction media. Silver elution as a function of solution composition and time was measured using Atomic Absorption Spectroscopy. The source of silver and the composition of the extraction medium were found to strongly affect the release of silver. Apparent equilibria established between silver and halide-containing salts (e.g. chloride ions) were disrupted by the presence of 5% BSA. * Tritec Silver by Milliken Healthcare Products LLC, Spartanburg, SC