Fabricating a PDA-NOate@CuS coated NIR-activatable titanium implant to realize simultaneous antiinfection and osseointegration

Abstract

Titanium has been widely used as a bone implant material due to its high mechanical strength and good biocompatibility. However, implant-related infections and insufficient osteogenic activity can lead to implant failure or delay patient recovery. With this in mind, we fabricated one multifunctional implant coating material, PDA-NOate@CuS. In the as-developed material, CuS, deposited in the outermost layer, not only significantly improved the photothermal properties of polydopamine (PDA), but also released Cu ions to effectively prevent bacterial adhesion. The NO-donor (NOate) under near-infrared irradiation generated NO which strengthened the antibacterial effect of materials. The in vitro antibacterial experiments proved that PDA-NOate@CuS displayed an excellent S. aureus and E. coli inhibitory effect. MC3T3-E1 cell experiment results showed that PDA-NOate@CuS promoted cell adhesion, growth and mineralization. Moreover, the in vivo study demonstrated that a titanium implant coated with Ti@PDA-NOate/CuS markedly enhanced osseointegration and inhibited infection, with good biocompatibility. The present study paves the way for developing novel materials for implant modification, which would benefit the treatment of orthopedic disease.