Ma Zuwei, Gao Changyou, Gong Yihong, Shen Jiacong
Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
J Biomed Mater Res B Appl Biomater. 2003 Oct 15;67(1):610-7. doi: 10.1002/jbm.b.10049.
Three-dimensional poly(L-lactic acid) (PLLA) scaffolds with high porosity and pore size ranging from 150 to 700 microm were conveniently prepared with paraffin spheres used as porogen. PLLA/1,4-dioxane solution containing a given amount of paraffin spheres was frozen at -25 degrees C to obtain a solidified mixture, followed with freeze drying and subsequent leaching with hexane to remove the 1,4-dioxane and paraffin spheres, respectively. The fabricated PLLA scaffolds were highly porous with evenly distributed and interconnected pores. The microstructures of the PLLA scaffolds as a function of paraffin-sphere size, paraffin-sphere dosage, and PLLA concentration were characterized by confocal laser scanning microscopy (CLSM) and scanning-electronic microscopy (SEM). To improve the cytocompatibility of the bioinert material, a hybrid PLLA scaffold containing Type I collagen was prepared by pressing the collagen solution into the scaffold under reduced pressure. The amounts of the collagen introduced in the scaffolds were detected by ninhydrin method. The distribution of the collagen in the scaffolds was studied with CLSM. Finally, in vitro cell culture was performed by injecting a chondrocyte suspension into the scaffolds. The results showed that the chondrocytes were more evenly distributed and more spread out in the collagen-modified PLLA scaffolds than in the unmodified ones.
以石蜡球为致孔剂，方便地制备了具有高孔隙率且孔径范围为150至700微米的三维聚（L-乳酸）（PLLA）支架。将含有一定量石蜡球的PLLA/1,4-二氧六环溶液在-25℃下冷冻以获得固化混合物，随后进行冷冻干燥，再用己烷浸提分别除去1,4-二氧六环和石蜡球。制备的PLLA支架具有高度多孔性，孔分布均匀且相互连通。通过共聚焦激光扫描显微镜（CLSM）和扫描电子显微镜（SEM）对PLLA支架的微观结构作为石蜡球尺寸、石蜡球用量和PLLA浓度的函数进行了表征。为了提高这种生物惰性材料的细胞相容性，通过在减压下将胶原蛋白溶液压入支架中制备了含I型胶原蛋白的复合PLLA支架。用茚三酮法检测支架中引入的胶原蛋白量。用CLSM研究了胶原蛋白在支架中的分布。最后，通过将软骨细胞悬液注入支架中进行体外细胞培养。结果表明，与未改性的PLLA支架相比，软骨细胞在胶原蛋白改性的PLLA支架中分布更均匀且铺展得更开。
