具有抗凝功能的可交联四臂星形聚己内酯的合成及其电纺丝加工的初步研究

Synthesis and Characterization of Cross-link and Anticoagulant Heparinized Four-arm Star-shape Poly(ε-caprolactone) and a Preliminary Study on Its Electrospinning

采用季戊四醇/辛酸亚锡引发体系通过开环聚合制备了四臂星形聚己内酯。将丙烯酰氯和肝素分别引入到四臂聚己内酯的端基上,以赋予材料可交联和抗凝性能。采用GPC、红外、核磁等表征了四臂星形聚己内酯的结构与性能。静态接触角和吸水率测试结果显示接枝肝素后聚己内酯的亲水性明显增强。采用紫外定量表征了肝素化聚己内酯表面的肝素含量,体外凝血时间的明显延长说明了肝素化后材料具有了抗凝性能。在添加适量光引发剂的情况下用紫外光对含有丙烯酰氯基团的肝素化聚己内酯进行了原位交联,力学测试表明光照后材料的拉伸强度明显提高。最后对材料通过静电纺丝技术成型管状支架作了初步研究,表明本文合成的抗凝可交联聚己内酯材料在血管组织工程领域具有良好的应用前景。

Four-arm star-shape poly（ε-caprolactone）s were prepared by Ring Opening Polymerization（ROP） with pentaerythritol/Stannous octoate as the initiator system. Photocurable and heparinized fourstar-shape poly（ε-caprolactone） （PCL） was synthesized by covalently attaching acryloyl chloride and heparin to the ends of four-arm star-shape poly（ε-caprolactone）s. The resulting polyester was also cross-linked under UV light with good mechanical properties. The properties of the four-arm star-shape poly （ε- caprolactone）s were tested by using GPC, IR and ^1H-NMR. The results of static contact angle and water absorption show that this heparinized PCL has better hydrophilic quality than its counterpart. The heparin content on the surface of this PCL was characterized by UV. The anticoagulant characteristics in vitro were evidenced by APTT test and the time of APTT test was obviously prolonged. The results of APTT test show that the heparinized material enjoys anticoagulant properties. The resulting polyester may also be cross- linked under UV light by adding an appropriate amount of photoinitiator. The results of mechanical tests show that the tensile strength is improved significantly after the exposure to the UV light. A preliminary study on its electrospinning properties was also carried out. The material can successfully be electrospun into tubular scaffolds with an uhrafine fiber structure. The cross-linked and anticoagulant heparinized four-arm star-shape poly （ε- caprolactone） enjoys a good application prospect in the field of vascular tissue engineering.