Zn-Li-Mn合金血管支架在体降解机制与生物学效应研究

锌在血管环境中具有适宜的降解速度和良好的生物相容性，近年来成为可降解支架材料的研究热点之一，但目前缺乏材料体系优化和支架植入实验，对锌基支架的在体降解机制、力学退化规律和生物学效应没有深入研究。基于前期优化的高强高塑Zn-Li-Mn合金体系（屈服强度243-369MPa，抗拉强度362-552MPa，延伸率53-103%），本项目将结合腐蚀学和细胞学评价，筛选最优合金成分配比，研究血管环境中的关键化学和力学因素（pH值、氧含量、应变、流体剪切力、脉动压力）对材料和支架降解行为的影响，探明金属离子协同释放与细胞应答之间的关系；通过动物实验，研究锌合金支架在体降解行为与力学退化规律，考察其降解产物对血管修复的组织学影响，揭示Zn-Li-Mn合金支架在血管修复过程中的在体降解机制和生物学效应，为可降解锌基材料在血管环境中的应用提供实验依据和理论基础。

Zinc performs appropriate degradation rates and good biocompatibility in vascular environments, which enables it to become one of the research focuses in biodegradable stent materials. However, very few studies have been done in optimizing zinc-based stent materials. More importantly, the degradation mechanism and mechanical degeneration of zinc-based stents, and their biological effects are unclear due to limited in vivo studies. The Zn-Li-Mn ternary alloys were optimized in our previous study, showing sufficient mechanical properties (yield strength of 243-369 MPa, ultimate tensile strength of 362-552 MPa, elongation to failure of 53-103%) for stent applications. The proposed research aims to optimize zinc alloy composition based on corrosion and cytological evaluations, investigate the influence of key chemical and mechanical factors (pH, oxygen content, strain, fluid shear force, and pulsating pressure) on the degradation behavior of materials and stents, and study the relationship between co-release of metallic ions and cellular responses (endothelial cells, smooth muscle cells, and macrophages). Animal tests will be performed to study the in vivo degradation behavior and mechanical degeneration of the Zn-Li-Mn alloy stent, and histological responses to its degradation products. This project will reveal the in vivo degradation mechanism and biological effects of the Zn-Li-Mn alloy stent during the vascular healing process, and provide the experimental and theoretical foundation for the application of biodegradable zinc-based alloys in vascular environments.