Fabrication of tantalum oxide layers onto titanium substrates for improved corrosion resistance and cytocompatibility

Due to its good biocompatibility and chemical stability, tantalum attracts much attention for biomedical applications, however, limited by its relatively high cost. In this study, tantalum oxide layers were deposited onto titanium (Ti) substrates with polymer-assisted deposition (PAD) technique to improve their corrosion resistance and cytocompatibility. Scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scratch tests and water contact angle measurement proved the successful formation of tantalum oxide layers onto the surfaces of Ti substrates. The potentiodynamic polarization curves revealed that the formed tantalum oxide layers improved the corrosion resistance of Ti substrates. Moreover, the in vitro tests displayed that Ti substrates coated with 6 layers of tantalum oxide promoted proliferation, alkaline phosphatase activity, mineralization and osteogenic gene expressions (ALP, Col I, OC and OPN) of osteoblasts, respectively. The study affords an approach for the fabrication of Ti-based implant with improved corrosion resistance and cytocompatibility.