In Vitro Degradation Behavior, Mechanical Properties, and Cytocompatibility of Biodegradable Mg-1Zn-xSn Alloys

Abstract

The application of biodegradable alloys in orthopedic implants has gained widespread attention globally. Magnesium alloys with controllable degradation rate and suitable mechanical properties have been regarded as potential orthopedic implant material. In this paper, a Mg-1Zn-xSn (x = 0, 1.0, 1.5, 2.0 wt.%) ternary alloy was designed and its performance was investigated. Compared with the Mg-1Zn alloy, the Mg-1Zn-xSn alloys showed enhanced mechanical properties and in vitro degradation performance. Above all, the extruded Mg-1Zn-1.0Sn alloy exhibited an extremely low corrosion rate of 0.12 mm/y with a low hydrogen release of 0.021 mL/cm2/day, which can be attributed to the hydrogen release suppression effect caused by Sn and SnO2 formation in the surface of the alloy. The cytotoxicity of the Mg-1Zn-1.0Sn alloy was evaluated by the cell counting kit-8 (CCK-8) method, the results of which show that its cytotoxicity grade is zero, and the MC3T3-E1 cells spread well on the alloy surface. The findings in this paper demonstrated that Mg-1Zn-1.0Sn is a potential candidate for biodegradable material in the orthopedic implant field.