Abstract：
Blood-contacting materials with good mechanical property, excellent anticoagulant function and promoting effect on endothelialization are in great demand for clinical application such as vascular grafts in treating cardiovascular diseases. In this study, electrospinning nanofiber scaffolds of polycaprolactone (PCL) were functionalized by oxidative self-polymerization of dopamine (PDA) on the surface followed by the modification of anticoagulant recombinant hirudin (rH) molecules. The morphology, structure, mechanical property, degradation behavior, cellular compatibility and blood compatibility of the multifunctional PCL/PDA/rH nanofiber scaffolds were evaluated. The diameter of the nanofibers was between 270-1030 nm. The ultimate tensile strength of the scaffolds was around 4 MPa and the elastic modulus increased with the amount of rH. The degradation tests in vitro indicated that the nanofiber scaffolds began to crack on the 7th day, but still maintained the nanoscale architecture within a month. The cumulative release of rH from the nanofiber scaffold was up to 95.9 % at 30th day. The functionalized scaffolds promoted the adhesion and proliferation of endothelial cells, while resisting platelet adhesion and enhancing anticoagulation effects. The hemolysis ratios of all scaffolds were <2 %. The nanofiber scaffolds are promising candidates for vascular tissue engineering.
摘要：
力学性能良好的血液接触材料，优良的抗凝血功能和促进内皮化的作用在血管移植等心血管疾病的临床应用中有着巨大的需求。在这项研究中,通过表面多巴胺（PDA）的氧化自聚，然后对抗凝血重组水蛭素（rH）分子进行修饰，使聚己内酯（PCL）的静电纺丝纳米纤维支架功能化。形态学,结构,机械性能，降解行为，评价了多功能PCL/PDA/rH纳米纤维支架的细胞相容性和血液相容性。纳米纤维的直径在270-1030nm之间。支架的极限拉伸强度为约4MPa,并且弹性模量随着rH的量而增加。体外降解试验表明，纳米纤维支架在第7天开始开裂，但仍在一个月内维持了纳米级架构。在第30天,rH从纳米纤维支架的累积释放高达95.9%。功能化的支架促进内皮细胞的粘附和增殖，同时抗血小板粘附和增强抗凝作用。所有支架的溶血率<2%。纳米纤维支架是血管组织工程的有希望的候选者。
