Interaction of Ti-6Al-7Nb alloy with simulated body fluid; a preliminary biocompatibility investigation

The current study aims to investigate the interaction of Ti-6Al-7Nb with simulated body fluid (SBF) in order to apply a preliminary biocompatibility investigation of this novel biomedical alloy, promising for orthopedic applications. Results of the static immersion tests conducted in SBF at body temperature demonstrated that Ca-P rich structures form on the Ti-6Al-7Nb alloy surfaces and the oxide layer formation-dissolution cycle reaches a stable state during immersion. Ion release levels were mostly below critical values except for the initial Al ion release level, which indicated the need for the presence of a stable protective layer on the alloy surface. The second set of static immersion experiments conducted in densified SBF demonstrated that, such a protective layer can rapidly form by biomimetic coating if followed by a preliminary surface treatment. Overall, Ti-6Al-7Nb alloys layers exhibit promising biocompatibility for orthopedic applications, especially with the presence of a stable protective layer.