具有表面微图形化胰肠吻合口支架的构建及研究

Construction and Study of Pancreaticojejunal Anastomotic Stents with Surface Micropatterns

胰十二指肠切除术后胰瘘极大地影响了患者的术后生存率及生活质量,目前临床上选择聚氨酯(TPU)管作为胰肠吻合口支架以应对这一并发症,但存在规格不匹配、易脱落等问题。受到树蛙趾垫表面微图形增强湿摩擦力的启发,设计了三种不同的微图形,并利用具有形状记忆功能的生物可降解材料制备了具有不同微图形的胰肠吻合口支架,然后对三种不同微图形的支架进行对比研究。使用6臂聚乙二醇作为引发剂,与己内酯发生开环聚合反应,加入丙烯酰氯接上双键,通过光交联,利用材料的形状记忆性能制备了印有表面微图形的6臂聚乙二醇-聚己内酯胰肠吻合口支架。考察了6臂聚乙二醇-聚己内酯支架的形状记忆性能、力学性能、亲疏水性等,证明该支架具有良好的形状记忆性能,有足够的刚性为胰管提供有效支撑,且能够引流胰液,维持胰管畅通。研究了模拟支架与胰管组织之间的摩擦行为,结果表明,表面微图形改性的6臂聚乙二醇-聚己内酯交联支架比TPU支架具有更大的湿摩擦力,同时对胰管组织造成的磨损较小,且正六边形柱体微图形为表面改性的最佳选择。最后评估了材料的生物相容性,证实材料具备植入体内的安全性,具有潜在的临床应用价值。

Pancreatic fistula after pancreaticoduodenectomy greatly affects the postoperative survival rate and quality of life of patients.At present,thermoplastic polyurethane elastomer rubber(TPU)tube is clinically selected as the pancreaticojejunal anastomotic stent to cope with this complication.However,there are problems such as mismatching specifications and easily falling off.In this work,a novel pancreaticojejunal anastomotic stent was made with biodegradable materials.Inspired by the micropatterns on the surface of tree frog toe pads to enhance wet friction,three kinds of micropatterns were designed to be modified on the surface of the stent,and the properties were compared.Using 6-arm polyethylene glycol as an initiator,ring-opening polymerization was performed withε-caprolactone,and acryloyl chloride was added to connect the double bond.The 6a PEG-PCL stent for pancreaticojejunal anastomosis crosslinked by light was prepared by using shape memory properties of the material.We evaluated shape-memory performance,mechanical properties,and hydrophilicity of the 6a PEG-PCL stent.It is proved that the stent had good shape memory performance.And this stent is rigid enough to provide effective support for the pancreatic duct.It can drain pancreatic juice and maintain the patency of the pancreatic duct.The friction behavior between the stent and the pancreatic duct tissue was simulated.The results showed that the 6a PEG-PCL stent modified by surface micropatterns had greater wet friction than the TPU stent and caused less wear to the pancreatic duct tissue.It is showed that the regular hexagonal pillar micropattern was the best choice for surface modification.Finally,we evaluated the biocompatibility of the material and the safety of the material was confirmed.Therefore,6a PEG-PCL stent had potential clinical application value.