几丁糖—聚乳酸复合生物材料神经导管的预构

Facrication of a nerve chonduit with a combined chitosan and PLA

目的:神经导管修复周围神经损伤,作为一种新的周围神经损伤修复方法显示出广阔的应用前景。本实验将几丁糖、聚乳酸两种材料结合,试图研制出一种理化性质、生物相容性俱佳的神经导管材料。材料和方法:第一部分:几丁糖—聚乳酸复合生物材料的研制及其物理性能测试。将2%几丁糖与0.5%聚乳酸以不同的比例化合反应后制成导管。力学实验检测不同比例制成导管的强度和韧性,根据实验结果选择最佳比例,并进一步测定该复合材料的其它物理性能。第二部分:几丁糖—聚乳酸复合生物材料的生物相容性检测。用细胞增殖度实验评价新材料的细胞毒性。用最大剂量法豚鼠致敏实验测试新材料致敏性。结果:2%几丁糖与0.5%聚乳酸以5:1(体积比)比例混合反应制成的新材料,其各项物理性能符合制备神经导管要求。在细胞毒性实验中,复合材料浸提液培养2天后及5天后,细胞相对增殖度(RGR)为83.67%,96.41%。致敏实验显示新复合材料浸提液致敏率为0级。实验证明新复合材料无细胞毒性、无致敏性。结论:几丁糖、聚乳酸通过适当比例结合制作的复合生物材料具有良的物理性能及生物相容性,符合制备神经导管的理化要求。

Objective: Nerve conduit, a new way to repair peripheral nerve, has good prospect. In this study, the PLA was combined with chitosan as a novel material to make nerve conduit, which is expected to have ideal physical property and biocompatibility. Material and methods: In part one, mix chitosan and PLA together to form a new material matching physical demand. 2% chitosan and 0.5% PLA was combined in different ratio to form the conduit. Mechenical test was studed on the conduits with different ratio, in order to understand which ratio was best for the intensity and tenacity. In part two, the biocompatibility of novel chitosan-PLA composite biodegradable material was tested. The ratio of 3T3 cell proliferation was observed to determine the cytotoxicity of novel material. The novel material’s sensitization was tested by using sensitizing test in the guinea pig. Results: (1)The novel material with 2% chitosan and 0.5% PLA at the ratio of 5:1 appeared good physical character matching the requirement of nerve conduits. (2) In the cytotoxicity test, the cell proliferation is 83. 67% after 48 hours, 96.41% after 5 days, which corresponded the standard of GB/T, demonstrating no cytotoxicity of the novel material. In the sensitizing test, the sensitization rate of the new material was zero in the guinea pig. Conclusion: The chitosan-PLA composite biodegradable material in approrite ratio, which has good physical character and good biocompatibility, is suit to make nerve conduits.