两种软骨组织工程新型复合支架材料初步研究

Primary study on two new types of composite materials for cartilage scaffold

目的利用聚谷氨酸苄酯-co-聚谷氨酸（PBLG-co-PGA）改性2种常规的生物可降解材料（胶原与壳聚糖），比较其性能及生物相容性，探索其用于软骨组织工程的可行性。方法用PBLG-co-PGA改性胶原和壳聚糖，对改性前后的材料进行接触角、体外降解性能、拉伸强度、细胞黏附率及细胞相容性等性能的检测和比较。结果随PBLG-co-PGA含量的增加，PBLG-co-PGM／胶原、PBLG-co-PGA，毒聚糖复合材料的降解速度减慢，接触角逐渐减小，PBLG-co-PGA，胶原复合材料的拉伸强度增加。选用PBLG-co-PGA质量分数为30％的复合材料，以兔软骨细胞进行细胞黏附率和细胞相容性实验，与无PBLG-co-PGA的单纯胶原或单纯壳聚糖材料比较，细胞黏附率差异无统计学意义（P0．05）；但兔软骨细胞在PBLG-co-PGA／言聚糖复合材料上生长增殖优于其他3种材料（P〈0．05）。结论经PBLG-co-PGA改性后的壳聚糖和胶原材料，可以调节材料的降解速度，改善壳聚糖亲水性，增加胶原拉伸强度，并且有良好的细胞相容性。其中PBLG-co-PGA，瘩聚糖复合材料具有更好的促细胞增殖特性，可以作为一种新的组织工程软骨支架材料。

Objective To prepare two types of biodegradable modified materials （chitosan and collagen） and evaluate whether the new materials are suitable for tissue engineering cartilage. Methods Collagen and chitosan were both modified by poly-γ-benzyl-L-glutamate-eo-glutamine acid （PBLG-co-PGA） with different proportions. The contact angle, degradation rate, tensile strength, cell attachment and cytocompatibility were tested and compared. Results As the PBLG-co-PGA content varied, the degradation rates of PBLG-co-PGA composites became adjustable, the hydrophilicity of PBLG-co-PGA/chitosan was improved, and the tensile strength increased in PBLG-eo-PGA/collagen composite. The composites with 30% PBLG-eo-PGA were chosen for cytoeompatibility and cell attachment experiments. The rabbit condrocytes grew significantly better on PBLG-co-PGA/chitosan than on other three materials（P〈0.05）. Conclusion PBLG can improve the hydrophilicity, tensile strength and regulate the degradation rate of composite materials, and the cytocompatibility of the composites with 30% of PBLG is good, among which PBLG-co-PGA/chitosan can even promote cell proliferation. It could be a new choice of scaffold for tissue engineering cartilage.