Research of the change of the construction and biocompatibility of expanded polytetrafluoroethylene (ePTFE) graft surface modified with fibronectin and fibronectin fragments

本研究旨在通过纤维连接蛋白或纤维连接蛋白片段GRGDSP对ePTFE假体表面进行修饰，使这些多肽或蛋白质结合在一起，从而检测ePTFE假体的内皮效应。首先，我们研究了ePTFE假体表面的聚合技术。采用大气压辉光(APG)放电处理方法，成功地将ePTFE接枝物从疏水改性为与丙烯酸(AAC)或聚丙烯酸(PAA)亲水性。AAc或PAA的聚合开始在ePTFE表面发生，然后在多孔结构中继续进行。PAA比AAC对ePTFE的表面改性效果更好。外表面比内表面更亲水。用聚四氟乙烯薄膜包裹ePTFE外管，用相同的实验方法处理后，ePTFE内表面的改性明显增强，尤其是AAC的使用，但纤维粘连蛋白片段与改性后的ePTFE接枝不成功。我们无法找到这一进程失败的原因。

This research was started to examine the endothelialization effect of the ePTFE prosthetic graft whose surface is modified by uniting fibronectin or fibronectin fragment GRGDSP To unite these peptide or protein, the surface of the ePTFE graft should be polymerized with carboxyl substances.At first, we investigate the technique of polymerization of the surface of ePTFE graft. Atmospheric pressure glow (APG) discharge treatment was successfully applied to modify ePTFE grafts from being hydrophobic to being hydrophilic with acryl acid (AAc) or poly acryl acid (PAA). Polymerization of AAc or PAA began occurring on the surface of ePTFE and then continued within porous structures. The surfaces of ePTFE were more effectively modified by PAA than AAc. The outer surface was more hydrophilic than the inner surface. When the outer tube of ePTFE was wrapped with PTFE film and processed using the same experimental method, a markedly enhanced surface modification on the inner surface, especially with the use of AAc, was observed..However, connection of fibronectin fragment to the surface of modified ePTFE grafts was not successful. We could not reach the reason why this process failed.