摘要
Titanium and its alloys, as the most prevalent materials for orthopedic implants, face two critical challenges in clinical practice: inadequate osseointegration and susceptibility to bacterial infection. To resolve these issues, a multifunctional coating (TNT+XGPP) was developed on Ti implants via three steps: electrochemical anodization to construct TiO 2 nanotube (TNT), hydrothermal loading of bone-affinity Ga 3+ ions (TNT+XG) at different concentrations, and carbodiimide-mediated grafting of γ-polyglutamic acid (γ-PGA) via a polydopamine intermediate layer. The morphology, composition, surface wettability, and ion release behavior of the prepared coatings were thoroughly characterized. The coatings were assessed for early-stage osteoblast growth behavior, Ca-P apatite formation capacity, and antibacterial activity. The characterization results confirmed that Ga 3+ ions and γ-PGA were successfully incorporated into TiO 2 nanotubes, significantly enhancing hydrophilicity. The TNT+XGPP coating, in conjunction with the nanotubes, Ga 3+ ions at appropriate concentrations (5, 20, and 50 mM), and γ-PGA, not only facilitated osteoblast adhesion and proliferation, but also upregulated the expression of osteogenic functional factors (e.g., alkaline phosphatase, osteocalcin, and runt-related transcription factor-2). In contrast, an elevated concentration of Ga 3+ ions (100 mM) in the coating exerted a certain inhibitory effect against osteoblast growth. The TNT+XGPP coating accelerated the in-situ deposition of bone-like Ca-P apatite, attributing to the synergy of γ-PGA and Ga 3+ ions. The released Ga 3+ ions exerted remarkable antibacterial effects against E. coli and S. aureus , with their concentration positively associated with antibacterial activity. This work offers a novel strategy for enhancing the bone affinity and antibacterial properties of Ti-based orthopedic implants.
危险品化学品经营许可证（带存储）