Shanxi Key Laboratory of Biomedical Metal Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Shanxi Key Laboratory of Biomedical Metal Materials, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China.
Biomater Adv. 2022 Jul;138:212968. doi: 10.1016/j.bioadv.2022.212968. Epub 2022 Jun 3.
Bone repair materials with excellent mechanical properties are highly desirable, especially in load-bearing sits. However, the currently used ceramic- and polymer-based ones mainly show poor mechanical properties. Recently, biodegradable metals have attracted extensive attention due to their reliable mechanical strength and degradability. As biodegradable metals, zinc-based materials are promising due to their suitable degradation rate and good biocompatibility. Here, we fabricated biodegradable porous Zn scaffolds with relatively high mechanical properties by vacuum heating-press sintering using NaCl particles as space holders. The microstructure, actual porosity, compressive mechanical properties, in vitro degradation behavior and the vitality of osteoblasts of porous Zn scaffolds were tested and investigated. The results show the porosities of the prepared porous Zn scaffolds are ranging from 11.3 % to 63.3 %, and the pore sizes are similar to the size range of the screened NaCl particles (200-500 μm). Compressive yield strength of 14.2-73.7 MPa and compressive elastic modulus of 1.9-6.7 GPa are shown on porous Zn scaffolds, some of which approach to that of cancellous bone (2-12 MPa and 0.1-5 GPa). Compared to bulk Zn, although the porous structures cause a partial loss of strength, the reliable mechanical properties are still retained. In addition, the porous structures not only greatly increase the degradation rate, but also promote the proliferation of osteoblasts. Based on these results, biodegradable porous Zn scaffolds (porosity in the 40 %-50 %) fabricated by vacuum heating-press sintering method show high application potential for clinical bone repair.
具有优异力学性能的骨修复材料是非常需要的，特别是在承重部位。然而，目前使用的陶瓷和聚合物基材料主要表现出较差的力学性能。最近，由于其可靠的机械强度和可降解性，可生物降解金属受到了广泛的关注。作为可生物降解金属，锌基材料由于其适宜的降解速率和良好的生物相容性而具有广阔的应用前景。在这里，我们使用 NaCl 颗粒作为造孔剂，通过真空加热-压烧结制备了具有相对较高力学性能的可生物降解多孔 Zn 支架。测试并研究了多孔 Zn 支架的微观结构、实际孔隙率、压缩力学性能、体外降解行为和成骨细胞活力。结果表明，所制备的多孔 Zn 支架的孔隙率为 11.3%-63.3%，孔径与筛选的 NaCl 颗粒（200-500μm）的尺寸范围相似。多孔 Zn 支架的压缩屈服强度为 14.2-73.7MPa，压缩弹性模量为 1.9-6.7GPa，其中一些接近松质骨（2-12MPa 和 0.1-5GPa）。与块体 Zn 相比，尽管多孔结构导致部分强度损失，但仍保留可靠的力学性能。此外，多孔结构不仅大大提高了降解速率，而且促进了成骨细胞的增殖。基于这些结果，通过真空加热-压烧结法制备的可生物降解多孔 Zn 支架（孔隙率为 40%-50%）在临床骨修复中具有很高的应用潜力。
