Bioactive UiO-66 coating on polydopamine-modified titanium implants

Engineering the surface of titanium (Ti) with bioactive coatings is an effective approach to address biofunctional limitations of Ti implants, including low bioactivity and poor tissue integration. Here, Ti substrates were functionalized with the UiO-66 metal-organic framework (MOF) via a polydopamine-assisted coating strategy to enhance cell-Ti implant interactions. The colloidal coating results in the formation of well-controlled surface with moderate hydrophilicity (water contact angle 70) and a reduced local surface roughness value (Ra 23 nm) relative to in situ growth (Ra 76 nm). The optimized coating strategy developed in this study reveals that MOF nanocrystal loading, surface roughness, hydrophilicity and wettability critically determine the biointerface behaviour and overall coating performance. The resulting hybrid morphology further promotes MC3T3-E1 cell viability on the implant surface while maintaining structural stability.