Improvement in antibacterial properties and cytocompatibility of titanium by fluorine and oxygen dual plasma-based surface modification

A versatile strategy to endow biomaterials with antibacterial ability and compromising cytocompatibility is highly desirable to solve serious infection problem of biomaterial implants. In this study, titanium (cp-Ti) was treated by a plasma enhanced fluorine (F) and oxygen (O) mono/dual chemical vapor deposition to obtain nano-functional coatings with improved antibacterial properties and biocompatibility. Using this platform, the anti-bacterial effect and the osteoblasts behavior were investigated in vitro. Meanwhile, the corrosion resistance of the fluoride coatings was also concerned. The fluorine-deposited samples can effectively kill Staphylococcus aureus and have adequate antibacterial properties. More importantly, the F and O dual-deposited coatings show the better sustaining antibacterial property after immersion in 0.9% NaCl solution up to 7 days than that of F monodeposited coatings. Besides, the cell compatibility tests indicate that the fluorine-deposited samples have no appreciable influence on the osteoblast viability and proliferation, but promote differentiation compared to the cp-Ti and O-Ti samples. F and O incorporation even shows some favorable effect on promoting cell spreading. Further, the electrochemical results demonstrate the F and O dual-deposited coating exhibiting an improved corrosion resistance due to the formation of titanium-oxygen compounds on surface. The F and O incorporated coating which provides improved antibacterial ability and biocompatibility has attractive applications in orthopedics, dentistry, and other biomedical devices.