Enhanced Bioactivity of Mg–Nd–Zn–Zr Alloy Achieved with Nanoscale MgF2 Surface for Vascular Stent Application

• Published in: ACS applied materials & interfaces 2015-03, Vol.7 (9), p.5320-5330
• Main Authors: Mao, Lin, Shen, Li, Chen, Jiahui, Wu, Yu, Kwak, Minsuk, Lu, Yao, Xue, Qiong, Pei, Jia, Zhang, Lei, Yuan, Guangyin, Fan, Rong, Ge, Junbo, Ding, Wenjiang
• Format: Article
• Language: English
• Subjects: Alloys - chemistry; Alloys - therapeutic use; Alloys - toxicity; Animals; Aorta, Abdominal - diagnostic imaging; Aorta, Abdominal - pathology; Biocompatible Materials - chemistry; Biocompatible Materials - therapeutic use; Biocompatible Materials - toxicity; Cell Adhesion - drug effects; Cell Proliferation - drug effects; Cell Survival - drug effects; Electrochemical Techniques; Fluorides - chemistry; Human Umbilical Vein Endothelial Cells; Humans; Magnesium Compounds - chemistry; Microscopy, Fluorescence; Prostheses and Implants; Rabbits; Stents; Surface Properties; Ultrasonography
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/am5086885

Magnesium (Mg) alloys have revolutionized the application of temporary load-bearing implants as they meet both engineering and medical requirements. However, rapid degradation of Mg alloys under physiological conditions remains the major obstacle hindering the wider use of Mg-based implants. Here we developed a simple method of preparing a nanoscale MgF2 film on Mg–Nd–Zn–Zr (denoted as JDBM) alloy, aiming to reduce the corrosion rate as well as improve the biological response. The corrosion rate of JDBM alloy exposed to artificial plasma is reduced by ∼20% from 0.337 ± 0.021 to 0.269 ± 0.043 mm·y–1 due to the protective effect of the MgF2 film with a uniform and dense physical structure. The in vitro cytocompatibility test of MgF2-coated JDBM using human umbilical vein endothelial cells indicates enhanced viability, growth, and proliferation as compared to the naked substrate, and the MgF2 film with a nanoscale flakelike feature of ∼200–300 nm presents a much more favorable environment for endothelial cell adhesion, proliferation, and alignment. Furthermore, the animal experiment via implantation of MgF2-coated JDBM stent to rabbit abdominal aorta confirms excellent tissue compatibility of the well re-endothelialized stent with no sign of thrombogenesis and restenosis in the stented vessel.