A silk-based coating containing GREDVY peptide and heparin on Mg-Zn-Y-Nd alloy: improved corrosion resistance, hemocompatibility and endothelialization

• Published in: Journal of materials chemistry. B, Materials for biology and medicine Materials for biology and medicine, 2018, Vol.6 (6), p.966-978
• Main Authors: Wang, Pei, Xiong, Pan, Liu, Jing, Gao, Shuang, Xi, Tingfei, Cheng, Yan
• Format: Article
• Language: English
• Subjects: Alloys; Biodegradability; Biodegradation; Blood coagulation; Cell culture; Clinical trials; Coronary artery; Corrosion; Corrosion prevention; Corrosion rate; Corrosion resistance; Corrosion resistant alloys; Electrochemistry; Endothelial cells; Endothelium; Hafnium base alloys; Heparin; Implants; Magnesium; Magnesium base alloys; Medical research; Muscles; Neodymium base alloys; Protective coatings; Regeneration; Restenosis; Silk; Silk fibroin; Smooth muscle; Stents; Surgical implants; Thromboembolism; Thrombosis; Umbilical vein; Yttrium; Zinc; Zinc base alloys
• ISSN: 2050-750X; 2050-7518
• DOI: 10.1039/c7tb02784b

Magnesium (Mg) alloys have been intensively investigated as potential absorbable coronary stent materials as their use avoids risks such as late inflammation and restenosis generated by permanent metallic implants. Besides that, clinical trials on coronary stents fabricated from Mg alloys have made great progress recently. However, the over-rapid corrosion rate, magnesium corrosion-induced thrombosis formation and delayed endothelium regeneration continue to be problematic for coronary artery stent therapy. In this study, silk fibroin blended with heparin and GREDVY (Gly-Arg-Glu-Asp-Val-Tyr) peptide was immobilized on a HF-pretreated MgZnYNd alloy surface via a polydopamine layer to improve its corrosion resistance, blood compatibility and endothelialization. Standard electrochemical measurements along with the long-term immersion results indicated that the functionalized MgZnYNd alloy had preferable anti-corrosion abilities compared with the bare MgZnYNd alloy. The modified surface exhibited outstanding hemocompatibility with reduced platelet adhesion, hemolysis rate and prolonged blood coagulation time. Human umbilical vein endothelial cell (HUVEC) and vascular smooth muscle cell (VSMC) co-culture results revealed more attached HUVECs on the functionalized samples than on the MgZnYNd alloy surfaces. The excellent corrosion retardation, hemocompatibility and re-endothelialization of the multi-functional coating indicate a promising method in the field of biodegradable magnesium-based implantable cardiovascular stents. This work explores a multifunctional surface coating with anti-corrosion, anti-coagulation and quick re-endothelialization properties for MgZnYNd alloy stent application.