Rapamycin-loaded nanoporous alpha-Fe2O3 as an endothelial favorable and thromboresistant coating for biodegradable drug-eluting Fe stent applications
Rapamycin-loaded nanoporous alpha-Fe2O3 as an endothelial favorable and thromboresistant coating for biodegradable drug-eluting Fe stent applications
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负载雷帕霉素的纳米孔 α-Fe2O3 作为内皮有利且抗血栓涂层，用于可生物降解的药物洗脱铁支架应用
DOI：
10.1039/c6tb02634f
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发表时间：
2017
影响因子：
7
通讯作者：
Zheng Yufeng
中科院分区：
文献类型：
--
作者：
Li Ming;Xu Xuchen;Jia Zhaojun;Shi Yuying;Cheng Yan;Zheng Yufeng
铁及其合金具有优良的力学性能和生物相容性，可用于制备先进的可降解心血管支架。然而，其固有的缓慢降解速率、血栓形成和支架内再狭窄阻碍了其临床应用。采用阳极氧化法在铁基体上成功制备了直径为30 ~ 70 nm的α-Fe 2 O3（赤铁矿）纳米管。这些纳米管涂层通过装载抗增殖药物雷帕霉素以加速再内皮化过程并通过简单的旋涂过程被PLGA涂覆以控制药物释放速率来充当药物仓库。静态浸泡实验表明，50 nm-Fe 2 O3纳米管阵列的腐蚀速率比纯Fe快，PLGA涂层有效地降低了载药的初始突释，并将雷帕霉素的释放时间延长至30 d。CCK-8测定和免疫荧光染色分析结果表明，包被样品上的内皮细胞（EC）显示出比血管平滑肌细胞（VSMC）更高的细胞活力，可能的结果是促进再内皮化和减少VSMC增殖。此外，表面改性的铁表现出非常好的血液相容性。目前的研究结果表明，在纯铁表面制备载雷帕霉素和PLGA涂层的Fe 2 O3纳米管可能是一种有前途的方法，以改善腐蚀速率，并加速可生物降解的心血管支架应用的铁的再内皮化。
Iron and its alloys can be potentially employed to fabricate advanced degradable cardiovascular stents due to their excellent mechanical and biocompatibility properties. However, their clinical applications are hindered by their inherent slow degradation rate, the formation of thrombosis and in-stent restenosis. In this study, vertically oriented and orderly arranged α-Fe2O3 (hematite) nanotubes with diameters ranging from 30 nm to 70 nm were successfully fabricated on iron substrates using an anodic oxidation approach. These nanotubular coatings acted as drug depots by being loaded with anti-proliferation drug rapamycin to accelerate the re-endothelialization process and being coated by PLGA through a simple spin-coating process to control the drug release rate. The static immersion test showed that the 50 nm-Fe2O3 nanotube arrays displayed a faster corrosion rate than pristine Fe, and the PLGA coating effectively reduced the initial burst release of the loaded drug and extended the rapamycin release time to 30 days. The CCK-8 assay and immunofluorescence staining analysis results indicated that the endothelial cells (ECs) on the coated samples showed higher cell viability than the vascular smooth muscle cells (VSMCs), with possible outcomes to promote re-endothelialization and decrease VSMC proliferation. In addition, the surface modified iron exhibited very good hemocompatibility. The current findings suggested that fabricating rapamycin-loaded and PLGA coated Fe2O3 nanotubes on a pure iron surface may be a promising method to improve the corrosion rate and accelerate the re-endothelialization of the iron for biodegradable cardiovascular stent applications.