Antibacterial protection of suture material by chlorhexidine-functionalized polyelectrolyte multilayer films

The formation of bacterial biofilms on the surface of implanted materials is a critical factor that may lead to chronic microbial infection and tissue necrosis. In the present study we analysed the stability of polyelectrolyte multilayer (ML) films on suture materials and the antibacterial effect obtained with chlorhexidine (CHX)-functionalized films built on different types of suture materials such as silk, polyester and copolymer of glycolide and L: -lactide. The comparison of Escherichia coli culture on glass coverslips and glass coverslips with ML and CHX showed at 24 h an inhibition of the bacterial relative luminescence (40.68%, P < 0.5) and at 48 h (99.46%, P < 0.001). In another way, simple soaking of suture material overnight in CHX digluconate 20% without polyelectrolyte films did not at all protect sutures from bacterial colonization but CHX-functionalized polyelectrolyte films, made from poly-L: -glutamic acid and poly-L: -lysine, inhibited Escherichia coli proliferation.