The effect of nano-size second precipitates on the structure, apatite-inducing ability and in-vitro biocompatibility of Ti-29Nb-14Ta-4.5Zr alloy.

Abstract

The apatite formation and in-vitro biocompatibility of Ti-29Nb-14Ta-4.5Zr (TNTZ) alloy reinforced by various nano-sized phases of α″, α, and ω in the β matrix have been studied. The electrochemical performances of the elaborated microstructures have been assessed through potentiodynamic polarization in the simulated body fluid (SBF) and interestingly, the β+ω specimen exhibited an extraordinary corrosion resistance compared to the others. This was attributed to the uniform distribution, spherical morphology and coherent interface of the ω nano-precipitates. The polarization tests in simulated body fluid showed the high tendency of apatite formation on the surface of the β- matrix contained ω precipitates. The in-vitro cytotoxicity analysis employing MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay showed >85% cell viability of the TNTZ alloy reinforced by nano-ω precipitations. Since this specimen showed the highest cell adhesion as well, it introduces this structure as a promising high potential candidate for biomedical applications due to its high corrosion resistance, biocompatibility, ultra-low cytotoxicity, and good cell adhesion.