NIR-responsive hydrogenated TiO2 nanoscale honeycomb surface pattern for rapid S. aureus biofilm elimination and enhanced osteogenesis

Abstract

Post-implantation infections significantly threaten clinical outcomes due to limitations in traditional antibiotic therapies and challenges in meeting the complex requirements for both bacterial eradication and osteoimmunomodulation. Current approaches rarely eliminate biofilms and enhance osseointegration without complex additional components. Herein, we developed a hydrogenated titanium dioxide (TiO2) nanoscale honeycomb surface pattern (H-NCs) by leveraging the inherent TiO2 component on titanium (Ti) surfaces. These engineered H-NCs with oxygen vacancies narrowed the TiO2 band gap to 1.32 eV, facilitating generation of reactive oxygen species (ROS) and mild hyperthermia for biofilm elimination under near-infrared (NIR) light. In vitro and in vivo results demonstrated rapid elimination of 99.94% and 91.58% of Staphylococcus aureus (S. aureus) within 15 min of NIR irradiation, respectively. Moreover, the 90-nm honeycomb-like surface structure directs macrophages by topographical cues, establishing a favorable osteoimmune microenvironment. In general, this novel modified surface may address the challenges of implant-related infection and enhancing osteogenesis simultaneously.