Ho Ming-Hua, Kuo Pei-Yun, Hsieh Hsyue-Jen, Hsien Tzu-Yang, Hou Lein-Tuan, Lai Juin-Yih, Wang Da-Ming
Department of Chemical Engineering, National Taiwan University,Taipei 106, Taiwan.
Biomaterials. 2004 Jan;25(1):129-38. doi: 10.1016/s0142-9612(03)00483-6.
Freeze-fixation and freeze-gelation methods are presented in this paper which can be used to prepare highly porous scaffolds without using the time and energy consuming freeze-drying process. The porous structure was generated during the freeze of a polymer solution, following which either the solvent was extracted by a non-solvent or the polymer was gelled under the freezing condition; thus, the porous structure would not be destructed during the subsequent drying stage. Compared with the freeze-drying method, the presented methods are time and energy-saving, with less residual solvent, and easier to be scaled up. Besides, the problem of formation of surface skin can be resolved and the limitation of using solvent with low boiling point can be lifted by the presented methods. With the freeze-extraction and freeze-gelation methods, porous PLLA, PLGA, chitosan and alginate scaffolds were successfully fabricated. In addition to the presentation of the morphologies of the fabricated scaffolds, preliminary data of cell culture on them are as well included in the present work.
本文介绍了冷冻固定和冷冻凝胶化方法，这些方法可用于制备高度多孔的支架，而无需耗时耗能的冷冻干燥过程。多孔结构是在聚合物溶液冷冻过程中形成的，随后要么用非溶剂萃取溶剂，要么在冷冻条件下使聚合物凝胶化；因此，多孔结构在随后的干燥阶段不会被破坏。与冷冻干燥法相比，所提出的方法节省时间和能源，残留溶剂更少，且更易于扩大规模。此外，所提出的方法可以解决表面皮层形成的问题，并消除使用低沸点溶剂的限制。通过冷冻萃取和冷冻凝胶化方法，成功制备了多孔聚乳酸（PLLA）、聚乳酸-羟基乙酸共聚物（PLGA）、壳聚糖和海藻酸盐支架。除了展示所制备支架的形态外，本文还包括了在这些支架上进行细胞培养的初步数据。
