新型肝素铁抗凝血涂层修饰血管内支架

实验于2006-12/2008-01在哈尔滨工业大学纳米医药与生物传感器实验室完成。采用静电吸引层层自组装的方法，在Ni-Ti合金表面组装Fe3+/肝素多层薄膜，使得材料表面形成稳定的糖铁络合物涂层。紫外可见光光度计、原子力显微镜和傅里叶变换红外光谱证实了Fe3+/肝素能够在Ni-Ti合金表面上交替沉积形成均匀的多层膜，并且具有很好的稳定性。研究表明，溶液的pH值和离子强度的增加能够显著增加涂层的增长速度。凝血酶失活、部分活化凝血酶原时间、溶血和血小板黏附试验等则证实了涂层具有良好的抗凝血性能和血液相容性，肝素并没有因与Fe3+结合而降低其抗凝血活性。说明该涂层可以用作血管内支架材料的表面修饰改性，在支架置入早期阻止血栓形成。

Novel iron heparin anticoagulation coating for intravascular stents

The experiment was performed at Nanomedicine and Biosensor Laboratory of Harbin Institute of Technology from December 2006 to January 2008. Fe3+/heparin multilayer films were assembled on the surface of Ni-Ti alloy by the layer-by-layer self-assembly, which made the stable glucose-Fe complex coating form on the surface of Ni-Ti alloy. The ultraviolet-visible absorption spectrophotometry, atomic force microscopy and fourier transform infrared spectroscopy proved that the Fe3+/heparin could form uniform multilayer films by alternative deposition on the surface of Ni-Ti alloy, and the coating had good stability. Studies showed that the increase of pH value and ionic strength in solution could obviously improve the increasing speed of the coating. The coating had good anticoagulation property and blood compatibility, which were proved by detection of thrombin inactivation, activated partial thromboplastin time, hemolysis test and platelet adhesion test. The heparin did not decrease its anticoagulation property after combined with Fe3+. The results suggested that the coating could be use for the surface modification of intravascular stents, and prevent thrombosis forming in early stage of stent implantation.