Biocidal and Antifouling Chlorinated Protein Films

Bacteria attach to the surfaces of medical devices and implants, resulting in life-threatening infections. Nonfouling coatings can be used to prevent adhesion of bacteria on the surface, while biocidal coatings kill the microbes. Combining nonfouling and biocidal properties can yield highly effective antimicrobial coatings. We demonstrate here a nanoimprint lithography (NIL)-based method to generate antibacterial coatings that both resist bacterial attachment and kill bacteria. In this strategy nanoimprint lithography was used to create water-stable films of bovine serum albumin (BSA) that are nonadhesive toward bacteria because of their negative/zwitterionic surface potential. Biocidal activity was then imparted through chlorination of cysteine sulfurs, providing slow release of chlorine and potent antimicrobial activity against pathogenic bacteria.