Bioinspired Materials Design Lab


An asymmetric surface coating strategy for improved corrosion resistance and vascular compatibility of magnesium alloy stents
Min-Ho Kang, Kwang-hee Cheon, Kyung-Il Jo, Ji-Ho Ahn, Hyoun-Ee Kim, Hyun-Do Jung*, Tae-Sik Jang
Publication date
Materials & Design
1-s2.0-S0264127520307176-main 2.pdf (3.0M) 24회 다운로드 DATE : 2020-11-10 11:46:20
Magnesium and its alloys are promising materials for biodegradable drug-eluting stent applications, but their rapid corrosion remains a major challenge for clinical practice. Considerable efforts have been made to develop an efficient surface coating that can provide higher Mg stent corrosion resistance, sustained drug-delivery capability, and vascular compatibility. Herein, we introduce poly(ether imide) (PEI) and poly(lactic-co-glycolic acid) (PLGA) as surface coating polymers for WE43 Mg-alloy stent. Using a sequential spray-coating method, we developed a novel asymmetric stent coating comprising an inner surface coated with a PEI single layer and outer/side surfaces coated with sirolimus-loaded PLGA/PEI double layers. PEI coating layer has excellent adhesiveness to WE43 surface and considerably improves WE43 corrosion resistance and in vitro endothelial cell compatibility. PLGA/PEI double coating layer ensures a low release rate of sirolimus and stable surface morphology during drug-release process. Only vascular smooth muscle cells are directly affected by sirolimus owing to the asymmetric geometry of PLGA/PEI double coating, which has a satisfactory anti-proliferation effect. These results indicate that the developed asymmetrically PEI- and PLGA/PEI-coated WE43 stents have significant potential for achieving enhanced re-endothelialization and suppressed in-stent restenosis in vascular stent applications.