Mussel-inspired self-assembly platform for staged implant osseointegration: Combining early anti-infection and late osteoinduction

Current implant systems still lack the ability to combat implant-associated infections (IAI) and insufficient osseointegration to reduce the risk of implant failure. There's an urgent need to develop an effective implant modification method to match the needs of different biological stages post-implantation, which requires anti-infection at the initial stage and osseointegration at the latter long-term stage. Here, we constructed a mussel-inspired layer-by-layer (LbL) self-assembly implant modification platform via tannic acid (TA), sequentially anchoring osteoanabolic drug (Abaloparatide, ABL) and antibacterial (Dimethylaminohexadecyl methacrylate, DMAHDM) to the Titanium (Ti) surface (Ti/ABL/DMAHDM). The Ti/ABL/DMAHDM exhibited outstanding antibacterial properties at the initial stage with an antibacterial rate of 100 % both in vitro (24 h) and in vivo (48 h). Moreover, it showed significant osteogenic induction ability at the latter long-term stage both in vitro (7 days and 14 days) and in vivo (4 weeks), accompanied by good biocompatibility. This TA-mediated self-assembly modification implants platform with staged regulation of anti-infection and osteoinduction offers potential clinical prospects for improving osseointegration after implantation.