Abstract
Magnesium alloy stents (MAS) show remarkable application potential for treating cardiovascular diseases, attributable to their superior mechanical properties and biodegradability. However, their clinical applications are significantly hindered by inadequate corrosion resistance and suboptimal blood compatibility. In this study, a multilayer coating was constructed on the Mg-Zn-Y-Nd (ZE21B) alloy to enhance its degradation rate, blood compatibility, and the capacity to promote endothelialization in the field of vascular stent applications. This coating comprised layers of magnesium fluoride, polydopamine, fucoidan, and the chemerin 15 (C15) peptide, achieved through a surface modification technique. The modified ZE21B alloy exhibited increased charge transfer resistance and decreased corrosion current density, suggesting a marked enhancement in its corrosion resistance. Furthermore, the modified alloy demonstrated exceptional blood compatibility, as evidenced by the comparatively low magnitudes of hemolysis, fibrinogen adsorption and denaturation, and platelet adhesion. After fucoidan and C15 peptide were grafted on samples, the coating notably promoted key biological behaviors of endothelial cells (ECs), including adhesion, proliferation, migration, and nitric oxide (NO) release. In contrast, it could efficiently restrain smooth muscle cell adhesion and proliferation. The ECs on the fucoidan and C15 peptide modified ZE21B alloy exhibited obvious competitive growth advantages over SMCs in a co-culture system. Furthermore, the introduction of the C15 peptide had endowed the ZE21B alloy with anti-inflammatory properties through regulating the M2 polarization of macrophages. This study offered a highly promising approach for the development of degradable MAS endowed with outstanding corrosion resistance and vascular histocompatibility.