新型聚己内酯/磷酸钙支架的制备及生物相容性研究

探讨新型聚己内酯(PCL)/磷酸钙(CPC)复合材料支架的制备方法及对骨髓基质细胞(BMSCs)的生物相容性。采用溶液共混法,利用可溶盐晶体做造孔剂,制备PCL/CPC复合材料支架,以单纯PCL和CPC支架为对照组,Q800型动态力学分析仪进行动态力学性能试验(DMA),采用排水法测量孔隙率;灭菌后通过与犬BMSCs体外共同培养后细胞形态、生长曲线、碱性磷酸酶(ALP)染色和半定量及骨钙素(OC)半定量等方法检测细胞在支架材料上的黏附、增殖及成骨分化情况,动物体内异位成骨检测其成骨情况。结果显示,复合材料的储能模量在PCL/CPC比例为7:3时达到最大,制得的材料孔径为250～350μm,多孔支架的孔隙率为70%～80%;BMSCs在新型PCL/CPC组、CPC组支架表面分布均匀,生长增殖明显较PCL组活跃(P<0.05);PCL/CPC组、CPC组BMSCs成骨行为与PCL组之间有显著差异(P<0.05)。动物体内异位成骨检测提示,4周时PCL/CPC组为13.78%±1.60%、CPC组BMSCs为15.29%±1.20%,成骨显著强于PCL组BMSCs的7.56%±2.20%(P<0.05),表明PCL和CPC的复合明显改善了两种材料的缺陷,获得的PCL/CPC支架具有良好的生物相容性,可与BMSCs共同构建具有成骨能力的三维立体组织工程化骨。

Study on Preparation and Biocompatibility of Novel Porous PCL/CPC Scaffolds

To investigate the preparation and biocompatibility of porous polycaprolactone/calcium phosphate cement(PCL/CPC) scaffolds in uses for bone marrow stromal cells(BMSCs),the scaffolds were fabricated by solution blending method,and water soluble salt crystals were used as pore-forming agent.The dynamic mechanical test(DMA) was conducted using Q800 dynamic mechanical analyzer,with the porosity measured by drainage method.BMSCs were implanted and cultured with PCL/CPC scaffolds in vitro,PCL and CPC scaffolds were taken as controls.The attachment,proliferation and differentiation of BMSCs were detected through morphological characters,growth curve,the activity of alkaline phosphatase(ALP) and osteocalcin(OC) and entopic bone formation in nude mice.Results showed that,storage modulus of the composite scaffold reached the maximum when the ratio of PCL to CPC was 7:3,the pore size of the material was 250~350 μm,and the porosity of the scaffolds reached 70%~80%.BMSCs attached to and grew better on the surface of porous PCL/CPC and CPC scaffolds than PCL scaffolds(P<0.05),and BMSCs proliferate,and function more actively on porous PCL/CPC and CPC scaffolds than on PCL scaffolds(P<0.05).More bone form in nude mice of PCL/CPC 13.78%±1.60% and CPC scaffolds 15.29%±1.20% than PCL scaffolds 7.56%±2.20%(P<0.05).In summary,PCL/CPC scaffolds have good biocompatibility for BMSCs to fabricate tissue-engineered bone in vitro.