Design and characterizations of novel biodegradable ternary Zn-based alloys with IIA nutrient alloying elements Mg, Ca and Sr

Apart from the industrial and automotive applications, Zn and Zn-based alloys are considered as a new kind of potential biodegradable material quite recently. However, one drawback of pure Zn as potential biodegradable metal lies in that pure Zn has quite low strength and plasticity. In the present study, three important IIA essential nutrient elements Mg, Ca and Sr and hot-rolling and hot-extrusion thermal deformations have been applied to overcome the drawback of pure Zn and benefit the biocompatibility of Zn-based potential implants. The microstructure, mechanical properties, corrosion behavior, hemocompatibility, in vitro cytocompatibility were studied systematically to investigate their feasibility as bioabsorbable implants. The results showed that the mechanical properties of the ternary Zn-1Mg-1Ca, Zn-1Mg-1Sr and Zn-1Ca-1Sr alloys are much higher than that of pure Zn, owing to both the alloying effects and thermal deformation effects. In vitro hemolytic rate test and cell viability test indicated that the addition of the IIA nutrient alloying elements Mg, Ca and Sr into Zn can benefit their hemocompatibility and cytocompatibility, which would further guarantee the biosafety of these new kind of biodegradable Zn-based implants for future clinical applications. (C) 2015 Elsevier Ltd. All rights reserved.National Basic Research Program of China (973 Program) [2012CB619102, 2012CB619100]; National Science Fund for Distinguished Young Scholars [51225101]; National Natural Science Foundation of China [51431002, 31170909]; NSFC/RGC [51361165101]; State Key Laboratory for Mechanical Behavior of Materials [20141615]; Beijing Municipal Science and Technology Project [Z131100005213002]; Project for Supervisor of Excellent Doctoral Dissertation of Beijing [20121000101]SCI(E)EIARTICLEyfzheng@pku.edu.cn95-1028