Hoque Md Enamul, San Wong Yoke, Wei Feng, Li Suming, Huang Ming-Hsi, Vert Michel, Hutmacher Dietmar W
Department of Mechanical, Materials and Manufacturing Engineering, University of Nottingham Malaysia Campus, Semenyih, Malaysia.
Tissue Eng Part A. 2009 Oct;15(10):3013-24. doi: 10.1089/ten.TEA.2008.0355.
Synthetic polymers have attracted much attention in tissue engineering due to their ability to modulate biomechanical properties. This study investigated the feasibility of processing poly(epsilon-caprolactone) (PCL) homopolymer, PCL-poly(ethylene glycol) (PEG) diblock, and PCL-PEG-PCL triblock copolymers into three-dimensional porous scaffolds. Properties of the various polymers were investigated by dynamic thermal analysis. The scaffolds were manufactured using the desktop robot-based rapid prototyping technique. Gross morphology and internal three-dimensional structure of scaffolds were identified by scanning electron microscopy and micro-computed tomography, which showed excellent fusion at the filament junctions, high uniformity, and complete interconnectivity of pore networks. The influences of process parameters on scaffolds' morphological and mechanical characteristics were studied. Data confirmed that the process parameters directly influenced the pore size, porosity, and, consequently, the mechanical properties of the scaffolds. The in vitro cell culture study was performed to investigate the influence of polymer nature and scaffold architecture on the adhesion of the cells onto the scaffolds using rabbit smooth muscle cells. Light, scanning electron, and confocal laser microscopy showed cell adhesion, proliferation, and extracellular matrix formation on the surface as well as inside the structure of both scaffold groups. The completely interconnected and highly regular honeycomb-like pore morphology supported bridging of the pores via cell-to-cell contact as well as production of extracellular matrix at later time points. The results indicated that the incorporation of hydrophilic PEG into hydrophobic PCL enhanced the overall hydrophilicity and cell culture performance of PCL-PEG copolymer. However, the scaffold architecture did not significantly influence the cell culture performance in this study.
合成聚合物因其调节生物力学性能的能力而在组织工程领域备受关注。本研究调查了将聚（ε-己内酯）（PCL）均聚物、PCL-聚（乙二醇）（PEG）二嵌段共聚物和PCL-PEG-PCL三嵌段共聚物加工成三维多孔支架的可行性。通过动态热分析研究了各种聚合物的性能。使用基于桌面机器人的快速成型技术制造支架。通过扫描电子显微镜和微计算机断层扫描确定了支架的总体形态和内部三维结构，结果显示在细丝连接处融合良好、均匀性高且孔隙网络完全连通。研究了工艺参数对支架形态和力学特性的影响。数据证实，工艺参数直接影响支架的孔径、孔隙率，进而影响其力学性能。使用兔平滑肌细胞进行了体外细胞培养研究，以调查聚合物性质和支架结构对细胞在支架上黏附的影响。光学显微镜、扫描电子显微镜和共聚焦激光显微镜显示，在两个支架组的表面以及结构内部均有细胞黏附、增殖和细胞外基质形成。完全连通且高度规则的蜂窝状孔隙形态支持通过细胞间接触实现孔隙桥接以及在后期产生细胞外基质。结果表明，将亲水性PEG引入疏水性PCL中可增强PCL-PEG共聚物的整体亲水性和细胞培养性能。然而，在本研究中支架结构对细胞培养性能没有显著影响。
