锌合金作为新型的可降解金属材料展现出很好的应用前景，而具备三维连通孔隙结构的多孔锌支架则很有希望应用于骨组织工程.为了提高多孔纯锌支架的细胞相容性，采用化学转化法在多孔纯锌表面成功制备了Mg-P生物活性涂层，表征了涂层的形貌、厚度、成分和结合力，并研究了涂层对多孔纯锌的降解行为和生物相容性的影响.结果表明，Mg-P涂层由细小的条束状晶粒以一定的取向相互堆叠而成，厚度约为10 μm，且与纯锌基体之间结合力良好.经Mg-P涂层处理后多孔纯锌的Zn2+释放速率显著降低，细胞相容性得到了明显改善，具有良好的应用前景.
Recently, zinc and its alloys are proposed as a new generation of biodegradable metal for medical implant. Particularly, porous Zn-based scaffolds with 3D interconnected pore structure were considered as promising candidates for bone tissue engineering scaffold. In order to improve the cytocompatibility of porous Zn scaffold, a bioactive Mg-P coating was firstly prepared on the surface of porous pure Zn scaffold utilizing a chemical conversion method. The morphology, thickness, composition and bonding force of the Mg-P coating were characterized, and the effect of the Mg-P coating on the degradation behavior and biocompatibility of the porous pure Zn scaffold were systematically studied. The results showed that the Mg-P coating consisted of tiny strip-like Mg-P grains which stack with a flower-like orientation. The thickness of the Mg-P coating was about 10 μm and the bonding force was good. The Mg-P coated scaffold presents significantly decreased Zn2+ releasing rate and obviously improved the cytocompatibility, which demonstrates great potential in bone tissue engineering application.
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