Innovative antibacterial coating by anodic spark deposition

Silver containing coating can represent a solution to the recurring problem of biofilm formation on implant surfaces. In this study, the development of a titanium oxide coating containing silver particles is reported. The coating was obtained on medical grade Ti-6Al-4V alloy by anodic spark deposition in an aqueous electrolyte. Surface characterization revealed a high specific surface area with a succession of flat plateaus and depressions. Silver was present all over the coating surface as small particles of sizes below 200 nm. When immersed in a liquid medium, the coating released silver ions at a constant rate over more than 15 days. The coating was able to show a complete killing of gentamicin-resistant Staphylococcus epidermidis within the first 12 h after inoculation.

► Silver is an effective antibacterial agent.
► Anodic spark deposition can be used for surface modification of titanium-alloy implants.
► The silver ions release rate stays constant for over 15 days.