Title: Bioinspired Polymeric Coating with Self-Adhesion, Lubrication, and Drug Release for Synergistic Bacteriostatic and Bactericidal Performance

Abstract: A combination of surface lubrication and antibacterial performance is highly imperative for biomedical implants in clinic. In this study, motivated by mussel-inspired adhesion, articular cartilage superlubrication, and drug-loading capacity of cyclodextrins, a new copolymer of p(DMA-MPC-CD) (namely PDMC) with self-adhesion, lubrication, and drug loading & release properties is developed for fabricating a versatile platform to construct a synergistic bacteriostatic/bactericidal surface. Specifically, the biomimetic coating is prepared via polydopamine mediated layer-by-layer (LBL) self-assembly method on the surface of titanium alloy (Ti6Al4V), and characterized by quartz crystal microbalance, X-ray photoelectron spectroscopy, and surface wettability to confirm the modification process. The biocompatibility evaluation using L929 cells shows that the coating, even with pre-loaded bactericide, presents satisfied biocompatibility in vitro. Additionally, the enhanced lubrication and bacterial resistance properties of copolymer-coated Ti6Al4V (Ti6Al4V@PDMC) are attributed to the tenacious hydration shell that is formed surrounding the zwitterionic phosphorylcholine charges. Furthermore, the bactericidal function of the biomimetic coating is successfully achieved by releasing the pre-loaded bactericide in a sustained manner, which effectively kills the adhered bacteria on the surface. In summary, the bioinspired surface functionalization strategy developed here may act as a universal and promising method for achieving enhanced lubrication and synergistic bacteriostatic/bactericidal properties in biomedical implants.