Neodymium-modified Mg-Zn-Zr magnesium alloy as a biodegradable osteogenic implant

Magnesium alloy is considered as one of the most promising biodegradable orthopedic implant material. However, the degradation rates and osteogenic property are difficult to control, which is detrimental to bone integration after implantation. Here, we report a neodymium (Nd) modification strategy for the improvement of osteogenic performance. This study investigated the microstructure and in vitro biological properties of Mg-Zn-Zr-based ZK60 alloy and its Nd-modified counterpart, ZNdK610. Microstructural analysis revealed that Nd addition refined grains and altered intermetallic phase morphology in ZNdK610. Biological assays showed that ZK60 promoted cell proliferation and differentiation, while Nd further enhanced adhesion and differentiation. Notably, 50% ZNdK610 media extracts significantly increased alkaline phosphatase activity in both cell lines. The improvement was attributed to Nd-induced upregulation of Runx2 expression at gene and protein levels, suggesting ZNdK610's potential as a superior biodegradable implant material due to its optimized microstructure and enhanced osteogenic properties.