Material Science and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, India.
J Biomed Mater Res B Appl Biomater. 2024 Sep;112(9):e35474. doi: 10.1002/jbm.b.35474.
Microstructure, mechanical, in vitro and in vivo behavior of extruded Mg alloys with varying Zn/Gd ratios, Mg-2Gd-2Zn-0.5Zr (Zn/Gd = 1), Mg-2Gd-6Zn-0.5Zr (Zn/Gd = 3), and Mg-10Gd-1Zn-0.5Zr (Zn/Gd = 0.1) were investigated. The results revealed that the major secondary phases such as W (MgZnGd), (Mg,Zn)Gd, LPSO (Long period stacking order) and I (MgZnGd) phase in alloys depended on Zn/Gd ratio. These second phases influenced the mechanical as well as biological characteristics of the alloys. Among studied alloys, Mg-10Gd-1Zn-0.5Zr alloy showed the highest yield strength and tensile strength of 270 (±9.29) and 330 MPa (±15.8), respectively, with a reasonably good elongation of 12% (±2.36). The presence of GdO in the degradation film of Mg-10Gd-1Zn-0.5Zr enhanced the resistance offered by the film, which resulted in its lowest biodegradation, better viability, and cell proliferation under in vitro condition. The short term (subcutaneous implantation in rats for 1 month) in vivo studies showed that the alloy Mg-10Gd-1Zn-0.5Zr degraded at a rate of 0.35 mm/y (±0.02) and did not induce any toxicity to the vital organs.
研究了具有不同 Zn/Gd 比的挤压 Mg 合金（Mg-2Gd-2Zn-0.5Zr（Zn/Gd=1）、Mg-2Gd-6Zn-0.5Zr（Zn/Gd=3）和 Mg-10Gd-1Zn-0.5Zr（Zn/Gd=0.1））的微观结构、力学性能、体外和体内行为。结果表明，合金中的主要次生相，如 W（MgZnGd）、（Mg，Zn）Gd、LPSO（长周期堆垛有序）和 I（MgZnGd）相，取决于 Zn/Gd 比。这些第二相影响了合金的力学和生物特性。在所研究的合金中，Mg-10Gd-1Zn-0.5Zr 合金表现出最高的屈服强度和拉伸强度，分别为 270（±9.29）和 330MPa（±15.8），伸长率为 12%（±2.36）。Mg-10Gd-1Zn-0.5Zr 降解膜中存在 GdO 增强了膜的阻力，导致其生物降解率最低、体外条件下的存活率和细胞增殖能力更好。短期（大鼠皮下植入 1 个月）体内研究表明，合金 Mg-10Gd-1Zn-0.5Zr 的降解速率为 0.35mm/y（±0.02），对重要器官没有任何毒性。
