Using submicroporous Ta oxide coatings deposited by a simple hydrolysis–condensation process to increase the biological responses to Ti surface

• A hydrolysis–condensation process produced a submicroporous Ta2O5 coating on Ti.
• Submicroporous Ta2O5 coating surface was negatively charged and hydrophilic.
• Submicroporous Ta2O5 coating enhanced protein adsorption.
• Submicroporous Ta2O5 coating enhanced bone marrow mesenchymal stem cell responses.
• Submicroporous Ta2O5 coating has a potential for bone implant applications.

This study used a simple hydrolysis–condensation process to prepare a tantalum pentoxide (Ta2O5) coating with submicroporous topography on a titanium (Ti) substrate. This coating is capable of enhancing biological responses. Characteristics of the surface coating, including morphology, composition, occurrence of functional groups, crystallographic structure, and degree of adherence, were analyzed. The release of Ti ions from the specimens in simulated blood plasma was also measured. The cytotoxicity of the specimens was determined according to ISO10993-5 specifications. We then evaluated biological responses, including fibronectin (FN) adsorption and human bone marrow mesenchymal stem cell (hBMSC) responses. Our results demonstrate that this simple hydrolysis–condensation process produced a negatively charged amorphous Ta2O5 coating with submicroporous topography and good adhesion to the Ti surface. Compared with an uncoated Ti surface, the Ta2O5 coating reduced the release of Ti ions and significantly enhanced FN adsorption and hBMSC responses, including cytoskeletal arrangement, cell adhesion, and cell proliferation. Thus, the proposed submicroporous Ta2O5 coating on a Ti surface has considerable potential for bone implant applications.