In vitro attachment of Staphylococcus epidermidis to surgical sutures with and without Ag-containing bioactive glass coating

The ability of a silver-doped bioactive glass (AgBG) coating to prevent bacterial colonization on surgical sutures was investigated in vitro. Bioactive glass powders, in the form of 45S5 Bioglass(R) and AgBG, were used to coat Mersilk(R) sutures using an optimized 'in house' slurry-dipping process. In vitro experiments were carried out using Staphylococcus epidermidis under both batch and flow conditions. While the traditional batch culture testing was used to determine the number of viable cells adhered to the surface, the flow-cell was used to visualize attachment and detachment over time. Under batch conditions of up to 180 min, statistically significant differences were observed in the colony forming units (CFU) per suture for both the coated and uncoated Mersilk(R) sutures. The results showed that the AgBG coating had the greatest effect on limiting bacterial attachment (8 x 10(2) CFU) when compared to the 45S5 Bioglass(R) coating (3.2 x 10(3) CFU) and the uncoated Mersilk(R) (1.2 x 10(4) CFU). Also under flow conditions differences were seen between the coated and uncoated sutures. Therefore, this preliminary study has demonstrated the quantification and visualization of bacterial attachment onto sutures in order to compare the antibacterial properties of Ag-containing bioactive glass coatings. The bactericidal properties imparted by Ag-containing glass open new opportunities for use of the composite sutures in wound healing and body wall repair.