丝素蛋白负电性增强改性及其对降钙素基因相关肽的加载能力

Negatively enhanced modification of silk fibroin and its load ability to calcitonin gene-related peptide

为提高丝素蛋白(SF)材料的快速内皮化能力,解决血管组织工程面临的血栓和内膜增生难题,将具有双向调控血管细胞生长功能的降钙素基因相关肽(CGRP)通过静电相互作用引入丝素蛋白材料表面。首先选用含有2个羧基的己二酸(AA)与丝素蛋白分子进行反应,采用流延法制备AA改性SF膜,研究了改性SF膜的结构和膜表面对CGRP分子的加载能力。结果表明:随着AA质量占比的增加,SF的Zeta电位逐渐减小,当SF与AA的质量比由100∶0变化为100∶2.5时,SF的Zeta电位由-2.66 mV下降至-5.4 mV;AA改性SF材料中引入了新的羧基和酰胺键,形成了以β-折叠结构为主的分子构象和SilkⅡ结晶结构;当SF与AA的质量比为100∶2.5时,AA改性SF膜表面静电作用加载的CGRP含量比未改性SF膜提高了9倍。

In order to improve the rapid endothelialization of silk fibroin(SF)materials,and prevent thrombosis and intimal hyperplasia in vascular tissue engineering,calcitonin gene-related peptide(CGRP),which has the function of bidirectional regulation of vascular cell growth,was loaded onto the surface of SF materials through electrostatic interaction.Adipic acid(AA)containing two carboxyl groups was used to react with SF molecules,and AA modified SF film was prepared by fluidization method.The structure of modified SF films and the loading capacity of CGRP on the film surface were studied.The results show that the Zeta potential of SF gradually decreases with the increase of AA mass ratio.When the mass ratio of SF and AA is changed from 100∶0 to 100∶2.5,the Zeta potential of SF decreases from-2.66 mV to-5.4 mV.The introduction of new carboxyl groups and amide bonds into AA modified SF materials formsβ-sheets and Silk II crystal structure.When SF and AA mass ratio increases to 100∶2.5,the content of CGRP loaded by electrostatic action get 9 times higher than that of unmodified SF film surface.