Near-infrared-driven Au-decorated polymer-metal protein microfibers with bacterial filtration ability for use in photothermal sterilization

Abstract The use of protein nanostructures can be widely applied in medical devices and biomaterials. However, the synthesis of photothermic bovine serum albumin (BSA) microfibers remains a challenge. In this study, novel protein microfibers (MS@BDA@Au) with bacterial filtration abilities were developed for use in inactivating bacteria under near-infrared (NIR) irradiation. Three types of MS@BDA microfibers were fabricated through the assembly of proteins with M2+ (Fe2+, Cu2+, Mn2+)/Na2S and the assistance of dopamine (DA). These were further decorated with gold nanoparticles to produce MS@BDA@Au microfibers, which exhibited a filtering capacity of 1 × 108 CFU bacteria per milligram, and obvious antibacterial effects at concentrations of 0.5 mg/mL. This paper presents a method that can be used in the functional micro-crystallization of proteins and the development of new types of protein fibers that can be employed in bacteria filtration and photothermal killing.