title: Enhanced in Vitro and in Vivo Performance of Mg-Zn-Y-Nd Alloy Achieved with APTES Pretreatment for Drug-Eluting Vascular Stent Application.
abstract: Bioabsorbable magnesium alloys are becoming prominent as temporary functional implants, as they avoid the risks generated by permanent metallic implants such as persistent inflammation and late restenosis. Nevertheless, the overfast corrosion of Mg alloys under physiological conditions hinders their wider application as medical implant materials. Here we investigate a simple one-step process to introduce a cross-linked 3-amino-propyltrimethoxysilane (APTES) silane physical barrier layer on the surface of Mg-Zn-Y-Nd alloys prior to electrostatic spraying with rapamycin-eluting poly(lactic-co-glycolic acid) (PLGA) layer. Surface microstructure was characterized by scanning electron microscope and Fourier transform infrared spectroscopy. Nanoscratch test verified the superior adhesion strength of PLGA coating in the group pretreated with APTES. Electrochemical tests combined with long-term immersion results suggested that the preferable in vitro anticorrosion behavior could be achieved by dense APTES barrier. Cell morphology and proliferation data demonstrated that APTES pretreated group resulted in remarkably preferable compatibility for both human umbilical vein endothelial cells and vascular smooth muscle cells. On the basis of excellent in vitro mechenical property, the animal study on the APTES pretreated Mg-Zn-Y-Nd stent implanted into porcine coronary arteries confirmed benign tissue compatibility as well as re-endothelialization without thrombogenesis or in-stent restenosis at six-month followup.
authors.affiliation: Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of cardiology, Peking University First Hospital , Beijing 100034, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Zheng
authors.affiliation: Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of cardiology, Peking University First Hospital , Beijing 100034, China.
authors.forename: Xingang
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of cardiology, Peking University First Hospital , Beijing 100034, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of cardiology, Peking University First Hospital , Beijing 100034, China.
authors.forename: Qiuping
authors.initials: Q
authors.lastname: Shi
authors.affiliation: Center for Biomedical Materials and Tissue Engineering, Academy for Advanced Interdisciplinary Studies, Peking University , Beijing 100871, China.|Shenzhen Research Institute, Peking University , Shenzhen 518055, China.
authors.forename: Tingfei
authors.initials: T
authors.lastname: Xi
authors.affiliation: Department of cardiology, Peking University First Hospital , Beijing 100034, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.affiliation: School of Materials Science and Engineering, Zhengzhou University , Zhengzhou 450002, China.
authors.forename: Shaokang
authors.initials: S
authors.lastname: Guan
mesh_terms: D000497:Alloys / Q000008:administration & dosage* / Q000737:chemistry*; D000818:Animals; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000737:chemistry; D002460:Cell Line; D054855:Drug-Eluting Stents; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D011437:Propylamines / Q000008:administration & dosage* / Q000737:chemistry*; D012377:Rodentia; D012821:Silanes / Q000008:administration & dosage* / Q000737:chemistry*; D013552:Swine; D013556:Swine, Miniature
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; C571250:Mg-Nd-Zn-Zr alloy; D011437:Propylamines; D012821:Silanes; C088294:3-aminopropyltrimethoxysilane
keywords: Mg−Zn−Y−Nd alloy; biocompatibility; coronary artery stent; in vitro degradation; surface modification