Design of a versatile platform on nanostructured Ti-Mo-Zr alloy surface with photothermal, antibacterial and osteoinductive properties for biomedical application.

Bacterial infection and inadequate osseointegration represent significant challenges in the application of titanium (Ti)-based bone implants. Surface modification presents a promising strategy to address these obstacles. Taking advantage of silver ions, black phosphorus nanosheets (BPNs) and polydopamine (PDA), this study developed a versatile platform on the surface of Ti-12Mo-10Zr (TMZ) alloy through a multiple surface modification process, including the anodic oxidation treatment of TMZ alloy, the preparation and addition of silver-loaded BPNs (BPNs/Ag), and the coating with PDA. Our results demonstrated that silver enhanced the stability of BPNs/Ag, which were successfully loaded to the nanostructure of oxidized TMZ surface. PDA coating conferred a pH-responsive property to the surface, prolonged the release of silver ions, and improved the photothermal performance. In acidic conditions that mimic bone defect microenvironment, the platform exhibited good photothermal performance, accelerated Ag⁺ release, enhanced antibacterial efficacy, and increased osteoinductivity. Taken together, due to its advantageous characteristics, the versatile platform provides a valuable solution to improve the surface performance of TMZ alloys.