Abstract: Objective　To construct a photothermal coating on a titanium surface with antibacterial cell adhesive properties, and to discuss its potential for clinical application. Methods　Photothermal polydopamine nanoparticle (PDA-NP) coatings were smeared on the surface of titanium-based biomaterials that required tissue integration to control infection. The antibacterial effect and cell adhesion of PDA-NP coating on titanium surfaces were evaluated by bacterial and cell co-culture models. Results　In vitro results showed that PDA-NP coating significantly enhanced cell adhesion and was conducive to cell proliferation. The adhered Staphylococcus aureus (S. aureus) on the titanium surface with PDA-NP coating could be killed by near-infrared (NIR) irradiation in 3 minutes. Besides, when MC3T3-E1 osteoblasts were inoculated on the titanium surface with PDA-NP coating after contaminated with S. aureus, the bacteria could be effectively killed after about 3 minutes of NIR irradiation with nearly no impairment to the cell adhesion behavior of MC3T3-E1. Conclusion　The PDA-NP photothermal coatings on the surface of titanium implants are significantly antimicrobial to control infection and promote cell adhesion, thereby promoting tissue integration and preventing collateral damage to the surrounding tissue at the site of infection.

Key words: Photothermal therapy, 　Titanium implant, 　Polydopamine, 　Osteogenic differentiation