以叔丁醇/蒸馏水(TBA/H2O)结晶体为模板,用冷冻干燥法制备出片层孔及圆形孔的两种孔型氧化铝支架材料,利用SEM观察支架形貌,测试了其生物性能,系统研究浆料溶剂组分含量、冷冻温度对支架材料形貌影响,探讨支架孔结构对成骨细胞附着的影响。结果表明:纯水浆料的多孔陶瓷支架形貌为片层状;加入叔丁醇后,片层间距减少;浆料中叔丁醇含量为90wt%时,孔道呈片层孔及圆形孔的双孔状;纯叔丁醇浆料的陶瓷支架形貌为圆形孔。双孔形貌支架的开孔孔隙率及总孔隙率最高,分别为78.5%和81.8%。孔径随冷冻温度的降低而减小。体外模拟实验表明:片层孔及圆形孔的双孔支架材料有利于细胞在其表面生长,材料表面细胞结构清晰,铺展形态良好。多孔支架材料对细胞的吸附率随孔径的增大而增大。冷冻温度为-10℃时,支架的压缩强度为90.6 MPa,符合骨组织工程中支架材料的强度值要求。
Using crystallized TBA/H2O(tert.-butyl alcohol/distilled water) solution as template,two kinds of Al2O3porous bioceramic scaffolds with the lamellar and circular macrospores were fabricated by the freeze casting.The morphology of scaffold was examined by SEM and the biologic performance was tested also.The influences of the mass fraction of the TBA and the freezing temperature on the structure and properties of the Al2O3scaffold were investigated systematically.The results show that the scaffold structure prepared from aqueous slurry is lamellar pores.The lamellar spacing decreases with increasing the content of TBA.The the morphology of pass is double-pores type,including lamellar and the circular pore,when the TBA content is 90wt%.The scaffold structure prepared from pure TBA is circular pores.The scaffold with dual-pores type owes the highest open porosity and total porosity,which are 78.5% and81.8%,respectively.The pore is decreased with the freezing temperature lowered.Vitro cellular assay indicate that the scaffold with the lamellar macrospores and the circular macrospores was conductive to the cell growth,the cell absorption rate gradually increases with the pore size increased.Cell surface structure clear,spreading in good shape.The compression strength is 90.6 MPa when the freezing temperature is-10 ℃,which meet the strength requirement of bone tissue engineering.