Osteogenic and antibacterial strontium-copper composite coating on SLA titanium surface

Balancing osteogenic activity and antibacterial efficacy on commercially pure titanium implant surfaces remains a significant challenge. In this study, a strontium-copper composite coating (SLA-Sr-Cu) was developed on sandblasted, large-grit, acid-etched (SLA) titanium surfaces via hydrothermal treatment and polydopamine-assisted deposition. XPS confirmed the successful incorporation of Sr and Cu as evidenced by characteristic Sr3d and Cu2p signals. ICP-OES verified controlled, sustained release of Sr 2+ and Cu 2+ . Surface characterization further showed favorable hydrophilicity and appropriate roughness. In vitro evaluations demonstrated that the SLA-Sr-Cu surface maintained rBMSCs adhesion and viability and significantly enhanced osteogenic differentiation, substantiated by increased ALP activity, upregulated expression of osteogenic genes ( ALP, Col-1, OPN ), and elevated extracellular matrix mineralization. Furthermore, the coating exhibited potent antibacterial properties attributable to Cu 2+ release, achieving inhibition rate over 40% for Staphylococcus aureus and inhibition rate over 80% for Porphyromonas gingivalis , and effectively suppressing initial bacterial adhesion and metabolic activity. Collectively, these findings highlight the merit of Sr-Cu co-modification for concurrent promotion of osteogenesis and antibacterial activity, offering a viable strategy for multifunctional dental implant surfaces.