中文摘要：

利用生物分子间的相互作用制备载VEGF的肝素-多聚赖氨酸（PLL）纳米颗粒,将该纳米颗粒固定于多巴胺涂覆的316L不锈钢表面,研究其对表面抗凝血性能以及内皮细胞行为的影响。通过阿辛蓝染色和甲苯胺蓝定量肝素的方法对改性表面的理化性质进行表征;用荧光染色法和扫描电镜观察表面血小板的粘附数量及形态;通过APTT检测不同样品表面的凝血时间;通过荧光染色法和CCK-8细胞增殖活性检测对改性表面的内皮细胞生长行为进行评价。结果显示,构建的纳米颗粒成功固定于316L不锈钢表面,改性后的表面具有良好抗凝效果（1h）,且样品体外浸泡0,5和15d后,依然保持良好的持续抗凝血性;同时,改性后的样品表面内皮细胞数量、形态、活性等生物学行为保持良好,具有明显促内皮再生的潜能。纳米颗粒引入心血管材料表面为其生物功能化提供了一种可行方法。

英文摘要：

The ideal biomaterials surface for the blood or vascular contacting should be hemocompatibility and en-dothelialization ability.This study focuses on improving the anti-coagulation and endothelial regeneration of 316L stainless steel （316L SS）surface by introduced VEGF-loaded heparin-poly-l-lysine （Hep-PLL）nanoparti-cles to its surface.The VEGF-loaded nanoparticles （NPV）were firstly constructed by electrostatic interactions. And the NPV were then immobilized on dopamine-coated 316L SS surface.The physicochemical properties of the modified surface were characterized by water contact angle assay,Alcian blue staining and toluidine blue O assay,etc.The adhesion behavior and morphology of platelets on the modified surfaces were evaluated by fluo-rescence staining and scanning electron microscope （SEM）.The clotting time were tested by APTT.The endo-thelial cell growth behaviors were evaluated by fluorescent staining and Cell Counting Kit-8 （CCK-8）.The re-sults revealed that the NPV were successfully immobilized onto 316L SS surface.The introduction of the loaded-VEGF nanoparticles obviously increased the blood compatibility due to the less platelet adhesion compared to the 316L SS surface.The modified surface also provided favorable endothelial regeneration according to the en-dothelial cells adhesion,proliferation and its biological activity based the CCK-8 measurements.Meanwhile,the modified surface still exhibited exciting antithrombogenic properties after immersed in PBS solutions for 5 and 15 d.Our results indicated that the surface modification of loaded VEGF heparin-poly-l-ly-Sine （Hep-PLL）nan-oparticles could be a promising strategy for cardiovascular contacting device.