Dual-functional antibacterial hybrid film with antifouling and NIR-activated bactericidal properties

The adhesion of pathogenic bacteria and the consequent formation of biofilms on biomedical materials and devices continue to be a significant concern in biomedical applications. Thus, it is critical to design antibacterial surfaces that limit bacterial adhesion and biofilm formation. The current study effectively fabricates a universal dual-functional antibacterial film with antifouling and photothermal bactericidal activity using a simple and ecologically friendly sequential deposition of polydopamine (PDA) layer and phase-transited bovine serum albumin (PTB) film. Because of the excellent antifouling characteristic of PTB film, hybrid surfaces can resist the initial attachment of majority of bacteria, however, a small number of bacteria adhering to the surface will be killed by near-infrared (NIR) irradiation due to the excellent photothermal effect of PDA layer. Compared to single-functional antibacterial surfaces with either antifouling or bactericidal qualities, this dual-functional surface demonstrated superior antibacterial performance and antibiofilm ability. Additionally, the hybrid surface can be utilized for many substrata despite the surface chemistry or topography. It exhibits negligible cytotoxicity and high histocompatibility, presenting a novel approach to eliminate surface-attached bacteria occurring in various healthcare applications.