Durable polymeric N-halamine functionalized stainless steel surface for improved antibacterial and anti-biofilm activity

Bacterial adhesion and colonization on stainless steel (SSL) based surgical instruments, hospital equipment, orthopedic implants, water purification and food processing units are a major problem. Imparting rechargeable antibacterial properties to SSL offers the prospect of a reusable and clean surface. In this study, the SSL surface was functionalized with a hydantoin-based antibacterial polymer that prevents bacterial adhesion and colonization. A new hydantoin monomer with three halogen binding sites, (Z)-N-((4-(2,5-dioxoimidazolidin-4-ylidene)methyl)phenyl)methacrylamide (DMPM), was synthesized, characterized and copolymerized with a commercially available 3-(methacryloyloxy)propyltrimethoxysilane monomer to develop the antibacterial polymer. The SSL surface was treated with piranha solution and the copolymer was covalently immobilized on the surface. The modified surface was examined for its antibacterial and anti-biofilm activity. The modified surface exhibited total kill (6 log reduction) of bacteria such as S. aureus and E. coli in 10 and 12 min respectively. The anti-biofilm activity of the modified surface was evaluated using a combination of fluorescence-based metabolic activity and scanning electron microscopy imaging suggested the comprehensive damage of S. aureus and E. coli biofilm architecture.