Bioinspired self-adhesive coating for surface functionalization of medical devices with lubrication and antibacterial properties

Surface functionalization with lubrication and antimicrobial properties can significantly enhance the therapeutic efficacy and minimize the infection risk in implanted medical devices, yet an effective combination of these features with a convenient preparation method remains a great challenge. Inspired by the self-adhesive capability of mussel, the superlubricity of articular cartilage, and the antimicrobial performance of coumarin derivative, in this study we developed a self-adhesive copolymer, PDAM, integrating both lubrication and antimicrobial functionalities. Using dopamine methacrylamide, 2-methacryloyloxyethyl phosphorylcholine, and 7-acryloyloxy-4-methylcoumarin as raw materials, the copolymer was successfully synthesized by free radical polymerization, which could be easily applied to the Ti substrates via a dipping method, forming a stable coating with enhanced lubrication and antimicrobial properties. The characterizations of X-ray photoelectron spectroscopy and fluorescence microscopy verified the desired self-adhesion and durability. The lubrication behavior was investigated via microscopic and macroscopic friction experiments utilizing atomic force microscopy and universal mechanical tester under various test conditions. Additionally, the antimicrobial property, a synergy of phosphorylcholine-induced hydration effect and antibacterial performance of coumarin derivative, was validated by extensive <em>in vitro</em> bacterial tests. In summary, the PDAM copolymer coating, much simple in its preparation and surface modification process, achieved excellent antimicrobial properties by bacteriostatic and anti-adhesion mechanisms, offering a promising potential for surface functionalization of implanted medical devices.