聚乳酸三维细胞支架降解行为研究

In vitro Degradation of Poly(D,L-lactic acid) Scaffolds

研究孔隙全连通的聚乳酸三维细胞支架,在磷酸盐缓冲溶液中的降解行为。支架采用致孔剂粘结———溶液浇铸/颗粒沥析技术制备,其孔隙率为88.88%,孔径分别为220μm^355μm和450μm^600μm。在37℃,pH7.4缓冲溶液中降解时,支架的重量逐渐降低,分子量呈线性关系下降;吸水率逐渐增大,第8周后趋于稳定,其中大孔径支架吸水率更高;降解过程中,支架外观尺寸和孔隙率基本维持不变。结果表明:孔隙间全连通的三维细胞支架,其自催化降解行为被明显抑制,支架的外观尺寸和孔隙率稳定,有利于获得外观尺寸稳定的工程化组织。

In vitro degradation of poly （D, L-lactic acid） 3-D scaffolds with complete-interconnectivity was investigated. The degradation experinents was conducted in pH7.4 phosphate-buffered saline at 37℃ for 30 weeks. PDLLA scaffolds applied in this experiment were fabricated through porogen bonding solvent casting/particulate leaching technique. Scaffohts with same initial porusity of 88.88 %, pore size range of 220μm ～ 355μm and 450μm ～ 600μm, were used as degradation specimens. As the degradation taking place in phosphate-buffer, the molecular weight and the weight of scaffolds decreased, and the water uptake increased. The water uptake of scaffold with pore size range of 220μm ～ 355μm was lower than that of pore size range of 450μm ～ 600μm. However,the dimension of the scaffolds remained constantly, These results suggested that the dimension and porosity of scaffolds can be remained constantly, and the autocatalytic effect can be suppressed through formation 3-D scaffolds with complete interconnectivity.