Biocompatibility of PCL/PLGA-BCP porous scaffold for bone tissue engineering applications

In this study, biomimic porous polycaprolactone/poly (lactide-co-glycolide) loading biphasic tricalcium phosphate (PCL/PLGA-BCP) scaffolds were fabricated successfully by solvent evaporation method. The distribution of biphasic tricalcium phosphate (BCP) in polycaprolactone/poly (lactide-co-glycolide) (PCL/PLGA) scaffold was confirmed by micro-computed tomography (micro-CT) scanning, scanning electron microscope (SEM) observation and Energy-dispersive X-ray Spectroscopy (EDS) analysis. The hydrophilicity of the scaffolds was confirmed by contact angle measurement. In in vitro experiments, proliferation of human bone marrow mesenchymal stem cell (hBMSCs) and its osteoblastic differentiation on scaffold were assessed for 1, 2 and 3 weeks using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, fluorescence observation, hematoxylin & eosin (H&E) staining and real-time polymerase chain reaction (RT-PCR). In in vivo experiments, ossification was observed using micro-CT analysis and histological staining.本研究通过溶剂挥发法（solvent evaporation method）成功制备了负载双相磷酸钙（biphasic tricalcium phosphate，BCP）的仿生多孔聚己内酯/聚乳酸-羟基乙酸共聚物（polycaprolactone/poly(lactide-co-glycolide)，PCL/PLGA）支架（简称PCL/PLGA-BCP支架）。通过显微计算机断层扫描（micro-computed tomography，micro-CT）、扫描电子显微镜（scanning electron microscope，SEM）观测与能量色散X射线能谱（Energy-dispersive X-ray Spectroscopy，EDS）分析，验证了双相磷酸钙在PCL/PLGA支架中的分布特征。采用接触角测量（contact angle measurement）证实了该支架的亲水性。体外实验阶段，分别于第1、2、3周，通过噻唑蓝比色法（3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide，MTT）、荧光观测、苏木精-伊红染色（hematoxylin & eosin，H&E）及实时聚合酶链式反应（real-time polymerase chain reaction，RT-PCR），评估了人骨髓间充质干细胞（human bone marrow mesenchymal stem cell，hBMSCs）在该支架上的增殖能力与成骨分化水平。体内实验阶段，则通过micro-CT分析与组织学染色观察骨组织形成情况。