In vivo biodegradation and biological properties of a Mg-Zn-Ca amorphous alloy for bone defect repair

Amorphous magnesium alloys, characterised by their unique disordered structure, exhibit exceptional mechanical properties and superior corrosion resistance. This study introduced a novel biodegradable Mg-Zn-Ca amorphous alloy. Immersion and electrochemical tests revealed uniform degradation in a simulated body fluid environment. The degradation products predominantly contained zinc and oxygen. After 28 days of immersion, the alloy’s structure largely remained intact, and it exhibited a minimal weight loss rate of 11.64 ± 1.85%, indicating its excellent corrosion resistance. In addition, the homogeneous and rapid degradation of the Mg-Zn-Ca amorphous alloy in rats (the residual volume at 12 weeks was 14.94 ± 5.05%, at least 2–3 times of the corrosion rate of immersion in vitro), thus increasing the bone volume/total volume and trabecular number. The new bone and the residual material surface showed good bone integration. Blood and organ tissue tests confirmed the in vivo biological safety. Therefore, Mg-Zn-Ca amorphous alloys have excellent potential as bone-repair materials, especially in load-bearing areas.