羟基丁酸与羟基辛酸共聚物一体化骨软骨组织工程支架的制备及性能*◆

背景：单层支架难以满足关节软骨损伤修复的要求,现提出骨软骨共同修复的一体化支架,以弥补了单一支架的部分缺陷。目的：以羟基丁酸与羟基辛酸共聚物为基础材料,羟基磷灰石等为复合材料研制一体化骨软骨组织工程支架,测试该支架的物理特性和细胞黏附性。方法：采用溶剂浇铸/颗粒沥滤法,以支架孔径、孔隙率、力学强度和细胞黏附生长率为检测指标,以羟基丁酸与羟基辛酸共聚物为连续相,通过改变致孔剂NaCl粒径和羟基磷灰石材料配比制备不同形态结构、力学强度和生物学功能的三层一体化骨软骨组织工程支架。结果与结论：致孔剂与支架材料的最佳质量配比分别为软骨层4.5/1,过渡层2.5/1,硬骨层3.5/1。扫描电镜观察显示支架的三层结构明显不同且紧密结合,其软骨层、过渡层、硬骨层的孔径分别为150~250 μm,≤60 μm,150~450 μm;孔隙率检测结果依次为84%,60%,75%;力学强度测定依次为2.93,6.43,4.30 MPa;支架对骨髓间充质干细胞无毒性,细胞黏附与生长状态良好。结果表明该一体化骨软骨组织工程支架具有仿生学特性,符合骨软骨组织工程支架的基本条件。关键词：羟基丁酸;羟基辛酸;共聚物;一体化支架;关节软骨缺损;骨软骨组织工程缩略语注释：PHBHO：poly(hydroxybutyrate-co-hydroxyoctanoate),羟基丁酸与羟基辛酸共聚体;HA：hydroxyapatite,羟基磷灰石doi:10.3969/j.issn.1673-8225.2012.16.004

Preparation and characterization of an integrative poly (hydroxybutyrate-co-hydroxyoctanoate) osteochondral tissue-engineering scaffold

BACKGROUND: Single-layer scaffold, however, is difficult to meet the requirements of articular cartilage injury and repair. The integrative scaffold makes up partial defects of a single-layer scaffold.OBJECTIVE: To prepare an integrative scaffold made of poly (hydroxybutyrate-co-hydroxyoctanoate)-hydroxyapatite to repair articular cartilage and subchondral bone defects. METHODS: The scaffold was prepared by solvent casting/particle leaching method, and its aperture, porosity, mechanical strength and cell adhesion growth were tested. RESULTS AND CONCLUSION: The optimal ratio of porogenic agent to scaffold material was 4.5/1 for the cartilage layer, 2.5/1 for the middle layer, and 3.5/1 for the bone layer. The porosity and pore size of the scaffold were 75% and 150-450 μm in the bone layer, 84% and 150-250 μm in the cartilage layer, 60% and ≤60 μm in the middle layer, respectively. The layers linked to be a whole one closely. The mechanical strength was 4.3, 6.43, and 2.93 MPa from the bone layer to the cartilage layer. The scaffold displayed good affinity to the cells. The technique of integrative scaffold made of poly (hydroxybutyrate-co-hydroxyoctanoate)-hydroxyapatite w as developed. The scaffold may be a competent candidate in application in articular cartilage damage repair.