Biocompatibility of a micro-arc oxidized ZrCuAlAg bulk metallic glass

Developing materials with high biocompatibility is key to improve the artificial medical implant. Bulk metallic glasses (BMGs) based on Zr have been proposed as promising biomaterials. The present work investigated the biocompatibility of Zr₄₆(Cu_4.5/5.5Ag_1/5.5)₄₆Al₈ BMG in depth by using several biomedical methods. Our results indicate that the BMG material treated by micro-arc oxidation technology (MAO) has good biocompatibility comparable to as-cast Ti–6Al–4V alloy. MAO introduced high density of pores and hydroxyapatite in the surface layer. At a moderate MAO voltage, 350 V, a surface with the highest density of uniform size pores and suitable surface roughness was obtained. The BMG material treated at 350 V thus demonstrated the strongest platelet adhesion, the best blood compatibility, the weakest oral mucous membrane irritation, the weakest inflammation, and fastest recovery of injured cells during the subcutaneous implantation tests, in comparison with the samples treated at other voltages. These results may advance the applications of Zr-based BMGs as biomaterials in future.