Mechanical properties, biodegradability and cytocompatibility of biodegradable Mg-Zn-Zr-Nd/Y alloys

Abstract Biodegradable magnesium alloys have been turned out to be a promising candidate for orthopedic applications. In this study, the mechanical properties, degradation behavior and cytocompatibility of Mg-Zn-Zr-Nd and Mg-Zn-Zr-Y alloys were studied in comparison with pure Mg. Mechanical tests showed that the strength and ductility of Mg-Zn-Zr-Nd and Mg-Zn-Zr-Y alloys were excellent. The corrosion resistance analyzed by electrochemical test and immersion test in alpha modified eagle (α-MEM) medium with 10 % fetal bovine serum (FBS) revealed the degradation of Mg-Zn-Zr-Nd and Mg-Zn-Zr-Y alloys were faster than pure Mg at an early stage but slowed down after long time immersion. The metal ion concentrations were consistent with the corrosion rate. Mg-Zn-Zr-Nd alloy shows better mechanical properties than pure Mg and better corrosion resistance than Mg-Zn-Zr-Y alloy. The direct and indirect in vitro tests with MC3T3-E1 cells demonstrate that Mg-Zn-Zr-Nd shows the best cytocompatibility and osteogenesis. The results suggest that Mg-Zn-Zr-Nd alloy shows an ideal combination of mechanical, corrosive and biological properties. In summary, these results implying the Mg-Zn-Zr-Nd alloy has great potential to benefit the future development of orthopedic applications.