Wu Linbo, Zhang Hong, Zhang Junchuan, Ding Jiandong
Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, China.
Tissue Eng. 2005 Jul-Aug;11(7-8):1105-14. doi: 10.1089/ten.2005.11.1105.
A novel method for the fabrication of complexly shaped three-dimensional porous scaffolds has been developed by combining modified compression molding and conventional particulate leaching. The resultant scaffolds of various shapes, including some shaped like auricles, were made of hydrophobic biodegradable and bioresorbable poly(D,L-lactic acid) (PDLLA) and poly(D,L-lactic-co-glycolic acid) (PLGA). A polymer-particulate mixture was first prepared by the conventional solvent casting method and then compressively molded in a specially designed flexible-rigid combined mold which facilitates shaping and mold release during the fabrication process. The molding was carried out at a moderate temperature, above the glass transition temperature and below the flow temperature of these amorphous polymers. A porous scaffold was then obtained after particulate leaching. The pores are highly interconnected and uniformly distributed both in the bulk and on the external surface of the scaffolds, and the porosity can exceed 90%. The mechanical properties of the resultant porous scaffolds are satisfactory as determined by measurements of compressive modulus and compressive stress at 10% strain. Good viability of cells seeded in the porous scaffolds was confirmed. This novel fabrication method is promising in tissue engineering because of its ability to produce precise and complexly (anatomically) shaped porous scaffolds.
通过将改良的压缩成型与传统的颗粒沥滤相结合,开发出了一种制造复杂形状三维多孔支架的新方法。所得的各种形状的支架,包括一些耳廓形状的支架,由疏水性可生物降解和可生物吸收的聚(D,L-乳酸)(PDLLA)和聚(D,L-乳酸-共-乙醇酸)(PLGA)制成。首先通过传统的溶剂浇铸法制备聚合物-颗粒混合物,然后在专门设计的柔性-刚性组合模具中进行压缩成型,该模具便于在制造过程中成型和脱模。成型在适中的温度下进行,该温度高于这些无定形聚合物的玻璃化转变温度且低于其流动温度。然后通过颗粒沥滤获得多孔支架。孔隙高度互连且在支架的整体和外表面上均匀分布,孔隙率可超过90%。通过测量10%应变下的压缩模量和压缩应力确定,所得多孔支架的力学性能令人满意。证实了接种在多孔支架中的细胞具有良好的活力。这种新颖的制造方法因其能够生产精确且复杂(符合解剖学)形状的多孔支架而在组织工程中具有广阔前景。