摘要
目的探讨具有纳米结构的聚己内酯/左旋聚乳酸共聚物(PCL-b-PLLA)作为半月板组织工程支架的可行性,及其与犬软骨细胞的体外生物相容性。方法开环聚合制备PCL-b-PLLA,液-液相分离技术制备纳米结构PCL-b-PLLA支架,固-液相分离技术制备PCL-b-PLLA支架,扫描电镜(SEM)观察材料结构;测定纳米结构支架体外降解率及力学强度。分离培养犬软骨细胞,取第3代软骨细胞接种于纳米结构PCL-b-PLLA(实验组)、PCL-b-PLLA(对照组)支架材料上进行三维培养6d,SEM观察软骨细胞的形态、粘附、生长状况;细胞支架复合培养3、6、12d后,Hoechst33258荧光法检测复合物中细胞DNA含量、BCA法测定蛋白质含量。结果实验组支架材料相对分子量150kD,压缩强度为72.6KPa,孔隙率为93%。SEM示实验组支架表面为多孔状,孔壁为纤维网状连接。其降解率起初始较慢,8周后降解速率明显加快。软骨细胞在实验组支架上粘附、增殖优于对照组。随时间延长细胞在支架材料上DNA和蛋白质含量逐渐增加,实验组DNA和蛋白质含量均明显高于对照组(P<0.01,P<0.05)。结论具有纳米结构的PCL-b-PLLA支架具有良好的生物力学性能及可降解性,可显著促进细胞粘附、增殖及合成代谢,有望成为一种较为理想的半月板组织工程支架材料。
Objective To study the material characterization of the nano-poly （a-caprolactone）- block-poly （L-lactic acid ） （Nano-PCL-b-PLLA） and the biocompatibility of Nano-PCL-b-PLLA with canine chondrocytes so as to explore its feasibility as a scaffold for the meniscus tissue engineering. Methods Nano-PCL-b-PLLA scaffold was made by liquid-liquid phase separation, and PCL-b-PLLA scaffold was made by solid-liquid phase separation. The materials＇ structure was observed by scanning electron microscope （SEM）. The degradation rate of nano-PCL-b-PLLA was detected by degradation test in vitro. Compressive strength was tested by biomechanics test. The canine chondrocytes were isolated and cultured. The passage 3 canine chondrocytes were seeded onto the PCL-b-PLLA scaffolds （control group） and nano- PCL-b-PLLA scaffolds （experiment group） cultured in the 3-dimensional environment. Cellular Morphological changes were observed by SEM after 6d. The protein content in seeded cells was determined by bicinchoninic acid assay （BCA）, and the content of DNA was quantified by using Hoechst33258 assay at 3 d, 6 d and 12 d, respectively. Results The relative molecular weight of nano-PCL-b-PLLA scaffold was 150 kD. The compressive strength was 72.6 kPa. Its poriness was 93%. It was found that the surface of the scaffold was porous and the wall of pore was nano-fibro-mash shape under the SEM. The degradation rate was slow at the beginning. Mter 8 week, the rate accelerated obviously. Under the SEM it was showed that the adhesion and proliferation of chondrocytes on the Nano-PCL-b-PLLA scaffolds was better than that on PCL-b-PLLA scaffolds. The chondrcytes DNA and protein contents increased with time. Moreover, the content of DNA and protein was higher in the experiment group than that in the control group （P 〈0.01, P 〈 0.05）. Conclusions The Nano-PCL-b-PLLA scaffold has satisfactory biomechanical characterization and degradation rate. It can promote cell adhesion, proliferation and anabolism. It will be an ideal scaffold for the meniscus tissue engineering.
出处
《中华关节外科杂志（电子版）》
CAS
2008年第6期40-43,共4页
Chinese Journal of Joint Surgery(Electronic Edition)
基金
广东省科技计划项目(2007B031001004
2005B34001003)
关键词
纳米结构
软骨细胞
生物相容性材料
组织工程
Nanostructures
Chondrocyte
Biocompatible materials
Tissue engineering
