Antibacterial ability and biocompatibility of fluorinated titanium by plasma-based surface modification

Biomaterial surfaces with satisfied antibacterial activity and appropriate cytocompatibility are a pressing clinical need for orthopedic and dental implants. Fluorine-containing biomaterials have been demonstrated to obtain antibacterial activity and osteogenic property, while the effect of fluorine chemical compositions on antibacterial property and cytocompatibility is rarely studied. To this end, the coatings with different fluorine chemical compositions on titanium surface were prepared by plasma treatment to verify the antibacterial ability and cytocompatibility of fluorinated surfaces. Their antibacterial ability was evaluated by using Staphylococcus aureus, and the cell compatibility was investigated with MC3T3-E1 cells in vitro. The results show that both fluorocarbon coating and metal fluorides coating exhibited a hydrophilic and nano-scaled roughness. Rather than the fluorocarbon coating, the coating composed of metal fluorides presented satisfied bactericide effect and excellent cytocompatibility. The antibacterial mechanism is associated with the metal fluorides and released fluoride ion. This work would provide novel sight in optimizing the surface modification method of fluorinated biomaterials for biomedical applications.