聚乳酸-聚乙醇酸共聚物/Ⅰ型胶原/壳聚糖复合人工硬脊膜的生物相容性

背景：聚乳酸-聚乙醇酸共聚物（poly-D,L-lactic-co-glycolic acid,PLGA）具有可吸收、细胞毒性小及硬度可调性的特点,符合作为人工硬脊膜材料的基本条件。但由于PLGA的表面缺乏功能性基团,生物相容性难以达到满意的要求。目的：通过加入Ⅰ型胶原和壳聚糖对PLGA进行表面改性,观察其作为人工硬脊膜材料的生物相容性。设计、时间及地点：对比观察实验,于2007-05/12在上海中医药大学生化与分子生物学实验室完成。材料：多孔PLGA膜由济南岱罡生物科技有限公司提供,Ⅰ型胶原蛋白由美国Sigma公司提供,壳聚糖由上海其胜生物制剂医疗器械公司提供,L929小鼠成纤维细胞由中国科学院上海生命科学院细胞所提供。方法：制作多孔PLGA膜、PLGA/Ⅰ型胶原复合膜（简称PG膜）、PLGA/Ⅰ型胶原/壳聚糖（9∶1）复合膜（简称PGC9∶1膜）、PLGA/Ⅰ型胶原/壳聚糖（5∶5）复合膜（简称PGC5∶5膜）。主要观察指标：各膜接触角、吸水率测定。L929小鼠成纤维细胞体外培养1,3,7d后纤维镜下观察细胞形态变化,并采用MTT法测定细胞毒性。结果：接触角分别为：PG膜0.05）。第3,7天,多孔PLGA膜与PG膜、PGC9∶1膜各组间,PGC9∶1膜与PGC5∶5膜组间差异有显著性意义（P〈0.05）。PGC9∶1膜可进一步改善复合膜的细胞黏附及增殖,PGC5∶5膜可抑制细胞增殖与分化。结论：PLGA膜的表面复合Ⅰ型胶原和壳聚糖可提高复合膜的生物相容性;PLGA/Ⅰ型胶原/壳聚糖（9∶1）复合膜在生物相容性方面基本符合人工硬脊膜的材料要求。

Biocompatibility of poly-D,L-lactic-co-glycolic acid/type-1 collagen/chitosan composite membrane as artificial spinal dura mater

BACKGROUND:Poly-D,L-lactic-co-glycolic acid (PLGA) that was characterized as absorbable,weak cytotoxicity,and adjustable hardness was ideal to be synthetized artificial spinal dura mater.Because of lacking of functional group at the surface of PLGA,it should be modified to fit the demand of satisfied biocompatibility.OBJECTIVE:To study the biocompatibility of PLGA membrane modified by type-Ⅰ collagen and chitosan.DESIGN,TIME AND SETTING:Contrast observation study,which was carded out in the Biochemistry and Molecular Biology Laboratory Shanghai University of Traditional Chinese Medicine from May to December 2007.MATERIALS:Porous PLGA membrane was provided by Jinan Banzheng Biology-Technology Co.,Ltd.,type-Ⅰ collagen by Sigma Company,USA,chitosan by Shanghai Qisheng Biological Agent Medical Apparatus and Instrument Company,and L929 L cell by Cellular Institute of Shanghai Academy of Life Science,Chinese Academy of Science.METHODS:PLGA membrane (P membrane),PLGA/type-Ⅰ collagen composite membrane (PG membrane),PLGA/type-Ⅰ collagen/chitosan (9:1) composite membrane (PGC 9:1 membrane) and PLGA/type-Ⅰ collagen/chitosan (5:5) composite membrane (PGC 5:5 membrane) were produced through a certain process.MAIN OUTCOME MEASURES:Contact angle,absorption rate and cytotoxicity were tested.Morphological changes of L929 L cell cultured for 1,3,and 7 days were observed under fiberscope.RESULTS:Contact angle was shown as PG membrane＜PGC 9:1 membrane＜PGC 5:5 membrane＜P membrane (P＜0.01 );absorption rate was shown as P membrane＜PGC 5:5 membrane＜PGC 9:1 membrane＜PG membrane (P＜0.01).L929 L cell was characterized as well distribution,expansion and appearance after inoculation of PG membrane,PGC 9:1 membrane and PGC 5:5 membrane.Cytotoxic experiment (MTT methods) showed that,on the 1st day,there was no significant difference in absorbency among groups (P＞0.05).On the 3rd and 7th days,there were significant differences between P membrane and PG membrane or PGC 9:1 membrane,and between PGC 9:1 membrane and PCK2 5:5 membrane (P＜0.05).PGC 9:1 membrane could further improve cell adhesion and proliferation,and PGC 5:5 membrane could inhibit cell proliferation and differentiation.CONCLUSION:Type-Ⅰ collagen and chitosan appended to the exterior of PLGA can enhance the biocompatibility of membrane.In terms of biocompatibility,PLGA/type-Ⅰ collagen/chitosan (9:1) composite membrane can be fit to the qualification as a type of material of artificial spinal dura mater.