Fabrication and evaluation of porous coatings doped with bioactive elements on titanium surfaces.

Objective: Although pure titanium (PT) and its alloys exhibit excellent mechanical properties, they lack biological activity as implants. The purpose of this study was to improve the biological activity of titanium implants through surface modification.

Materials and methods: Titanium was processed into titanium discs, where the titanium discs served as anodes and stainless steel served as cathodes, and a copper- and cobalt-doped porous coating [pure titanium model (PTM)] was prepared on the surface of titanium via plasma electrolytic oxidation. The surface characteristics of the coating were evaluated using field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and profilometry. The corrosion resistance of PTM was evaluated with an electrochemical workstation. The biocompatibility and bioactivity of coated bone marrow mesenchymal stem cells (BMSCs) were evaluated through in vitro cell experiments.

Results: A copper- and cobalt-doped porous coating was successfully prepared on the surface of titanium, and the doping of copper and cobalt did not change the surface topography of the coating. The porous coating increased the surface roughness of titanium and improved its resistance to corrosion. In addition, the porous coating doped with copper and cobalt promoted the adhesion and spreading of BMSCs.

Conclusions: A porous coating doped with copper and cobalt was prepared on the surface of titanium through plasma electrolytic oxidation. The coating not only improved the roughness and corrosion resistance of titanium but also exhibited good biological activity.