新型肝素化聚氨酯膜的制备与研究

A Novel Polyurethane Immobilized with Heparin

通过两步溶液聚合法合成表面含有羧基的聚氨酯(PU),并用1-乙基-3-(二甲基丙胺)碳二亚胺(WSC)对聚氨酯表面羧基进行活化后,在4℃下柠檬酸钠缓冲液中与肝素上氨基反应得到表面共价键接枝的肝素化聚氨酯膜。通过甲苯胺蓝染色法、红外光谱法等对肝素化前后结构特征进行表征,用静态水接触角、体外抗凝血性测试其生物相容性。结果表明:在pH=5.0的肝素柠檬酸钠缓冲液中反应96 h,聚氨酯表面肝素接枝率最高,接枝量达到1.92μg/cm2;同时,共价接枝肝素后接触角从61°降低到44°,并且抗凝血性能得到明显的改善。

Polyurethanes containing carboxyl group were synthesized by two-step solution polymerization. Heparin was immobilized on the PU surface via reacting between carboxyl group and the amino group in the heparin by covalent immobilization technology in heparin sodium citrate buffer at 4 ℃. The heparinized polyurethanes were investigated by FT-IR, water contact angle and antithrombin tests. Results show that the highest heparin content of PU surface is in heparin sodium citrate buffer （pH=5.0） for 96 h. The water connect angle is reduced from 61° to 44° after heparinization. Meanwhile, heparinization observably improves the blood anticoagulation of polyurethane.