Biodegradable stents made of magnesium (Mg) and its alloys have been developed to minimize persistent inflammation or in-stent restenosis, which are the main problems for permanent stents. However, their rapid corrosion behavior under physiological conditions leads to poor vascular compatibility and premature structural failure, which remains an important unsolved clinical problem. Herein, we demonstrate a new strategy for solving this problem by combining poly (ether imide) (PEI) coating and subsequent tantalum (Ta) ion implantation. The PEI coating covers the whole surface of the Mg stent uniformly via a spray coating technique and provides Mg with superior corrosion resistance and stable sirolimus-carrying ability. Ta ion implantation is conducted by a sputtering-based plasma immersion ion implantation technique only onto the luminal surface of the PEI-coated Mg stent. Its extremely short processing time (< 30 s) permits preservation of the PEI coating's corrosion protection ability and sirolimus loading characteristics. In addition, a Ta-implanted skin layer that forms on the topmost surface of the PEI coating plays an effective role in not only preventing a rapid release of sirolimus from the surface but also improving the PEI coating's surface hydrophilicity. Based on in vitro cellular response and blood compatibility tests, Ta ion implantation leads to the improvement of endothelial cell adhesion/proliferation and suppression of platelet adhesion/activation regardless of sirolimus loading. These results indicate that the combination of PEI coating and Ta ion implantation has significant innovative potential to provide excellent vascular compatibility and prevent in-stent restenosis and thrombosis.

已开发出由镁 (Mg) 及其合金制成的可生物降解支架，以最大限度地减少持续性炎症或支架内再狭窄，这是永久性支架的主要问题。然而，它们在生理条件下的快速腐蚀行为导致血管相容性差和结构过早失效，这仍然是一个重要的未解决的临床问题。在此，我们展示了一种通过将聚（醚酰亚胺）（PEI）涂层和随后的钽（Ta）离子注入相结合来解决该问题的新策略。PEI涂层通过喷涂技术均匀覆盖镁支架的整个表面，为镁提供了优异的耐腐蚀性和稳定的西罗莫司携带能力。Ta 离子注入是通过基于溅射的等离子体浸入离子注入技术进行的，仅在 PEI 涂层镁支架的管腔表面上进行。其极短的处理时间 (< 30 s) 允许保留 PEI 涂层的腐蚀保护能力和西罗莫司负载特性。此外，在 PEI 涂层最上表面形成的植入 Ta 的表层不仅可以有效防止西罗莫司从表面快速释放，还可以提高 PEI 涂层的表面亲水性。基于 在 PEI 涂层最上表面形成的植入 Ta 的表层不仅能有效防止西罗莫司从表面快速释放，还能提高 PEI 涂层的表面亲水性。基于 在 PEI 涂层最上表面形成的植入 Ta 的表层不仅能有效防止西罗莫司从表面快速释放，还能提高 PEI 涂层的表面亲水性。基于在体外细胞反应和血液相容性测试中，无论西罗莫司负荷如何，Ta 离子植入都会改善内皮细胞粘附/增殖并抑制血小板粘附/活化。这些结果表明，PEI 涂层和钽离子植入的结合具有显着的创新潜力，可提供出色的血管相容性并防止支架内再狭窄和血栓形成。