Surface Modification of Titanium by Cobalt-Containing Plasma Electrolytic Oxidation Promotes Osteogenic Response

Titanium (Ti) is a widely used metallic biomaterial in developing orthopedic implants or devices, but it is often encountered with a poor osteogenic response. In this study, the authors report the surface modification of Ti with cobalt (Co)-containing titanium dioxide (TiO2) coatings by plasma oxidation technique in order to enhance its cellular response. The results were compared between unmodified and surface modified Ti. The scanning electron microscopy (SEM) analysis showed that the surface coating was homogenous and porous throughout the test specimen. Indeed, the energy-dispersive X-ray spectrometry (EDS) analysis showed that the cobalt was evenly distributed on the Ti surface. It was also observed from the preliminary cell culture studies that the surfacemodified Ti has excellent cell compatibility and has promoted the adhesion and proliferation of osteoblasts when compared to the unmodified Ti. The present study clearly demonstrated that the Co-containing plasma electrolytic oxidation is an efficient technique for the surface modification of Ti in order to promote its osteogenic response.