组织工程用聚乳酸多孔支架的制备与性能

发布时间：2018-05-20 18:10

本文选题：组织工程 + 多孔支架　；参考：《湖北工业大学》2012年硕士论文

【摘要】：组织工程学的核心是构建细胞与多孔材料的三维空间复合体，以促进植入细胞的粘附、增殖、分化、新陈代谢等。因此，如何有效的制备出满足需要的多孔支架材料备受关注。在组织工程支架的制备方法中，溶剂浇铸/粒子沥滤法(SC/PL)以其对实验设备要求低、实验步骤操作简单、支架的孔隙率及孔径可控等优点而被广泛采用。但是，传统的SC/PL只适合制备2~3mm厚的薄层支架，本课题组采用自主发明的溶剂浇铸/真空挥发/粒子沥滤法(SC/VV/PL)制备PLA多孔支架，展开了以下三个方面的研究。 1.采用SC/VV/PL法制备三维多孔支架，支架的孔分布均匀，孔-孔连通性好，支架的孔径与所用致孔剂颗粒粒径相符；支架的孔隙率测试均大于89%，支架的压缩模量最小为1.95±0.2MPa，压缩模量随着孔隙率的增大而下降；L929细胞毒性测试结果证实支架不存在细胞毒性，另外，借助不同内径的玻璃管制模具，本方法还可制备管状多孔支架。 2.采用SC/VV/PL法制备孔径轴向梯度变化的三维多孔支架，支架孔隙率最小值为87.34±0.3%，最大为91.24±0.3%；最大孔径为453±18μm，最小孔径为166±41μm；压缩模量由第1层的2.12±0.08MPa到第13层的2.56±0.18MPa呈递增趋势；此外，率先使用墨汁渗透法表征了支架的孔-孔连通性，结果表明PLA支架内部及不同孔径的层与层之间具有良好的孔-孔连通性。 3.采用SC/VV/PL法制备孔径径向梯度变化的三维多孔支架，梯度多孔支架各层的平均孔径为175±30μm、256±25μm、341±23μm，孔隙率均大于87.9±1.2%，支架不同层的应力-应变曲线表明，在较小应力作用下，材料显示线性弹性行为，当应变继续增大(30%~40%)，应力较为均匀地增加，应变大于40%后，应力迅速增加；TGA测试结果证实支架不存在致孔剂和溶剂残留。综上所述，本论文以自主发明的SC/VV/PL法制备了PLA多孔支架，，该方法继承了传统的SC/PL方法的全部优点，并且克服了SC/PL方法只适合制备2~3mm厚的薄层支架的缺点，此外，SC/VV/PL法具有在真空下溶剂挥发更快更彻底、适合制备多种类型的支架等优点。
[Abstract]:The core of tissue engineering is to construct a three-dimensional complex of cells and porous materials to promote the adhesion, proliferation, differentiation and metabolism of implanted cells. Therefore, how to effectively prepare porous scaffolds to meet the needs has attracted much attention. In the preparation of tissue engineering scaffolds, solvent casting / particle leaching method (SC-P) has been widely used for its advantages of low requirements for experimental equipment, simple operation of experimental procedures, and controllable porosity and pore size of scaffolds. However, the traditional SC/PL is only suitable for the preparation of thin layer scaffolds with thick 2~3mm thickness. Our team prepared PLA porous scaffolds by solvent casting / vacuum volatilization / particle leaching method. The following three aspects have been studied. 1. Three-dimensional porous scaffold was prepared by SC/VV/PL method. The pore distribution of the scaffold was uniform and the pore to pore connectivity was good. The pore size of the scaffold was consistent with the particle size of the porous agent used in the scaffold. The porosity tests of the scaffolds were all greater than 89, and the minimum compression modulus of the scaffolds was 1.95 卤0.2MPa. The results of cell toxicity tests showed that the scaffolds did not have cytotoxicity by decreasing the modulus of compression with the increase of porosity. In addition, the mold was controlled by glass with different internal diameters. The method can also be used to prepare tubular porous scaffolds. 2. Three-dimensional porous scaffolds with axial gradient of pore diameter were prepared by SC/VV/PL method. The minimum porosity of the scaffold was 87.34 卤0.3 and the maximum was 91.24 卤0.3. The maximum pore size was 453 卤18 渭 m and the minimum pore size was 166 卤41 渭 m. The compression modulus increased from 2.12 卤0.08MPa in layer 1 to 2.56 卤0.18MPa in layer 13. The hole-pore connectivity of the scaffold was first characterized by using the ink permeation method. The results show that the PLA scaffold and the layers with different pore sizes have good pore-pore connectivity. 3. Three-dimensional porous scaffolds with radial gradient of pore diameter were prepared by SC/VV/PL method. The average pore size of each layer was 175 卤30 渭 m, 256 卤25 渭 m, 341 卤23 渭 m, and the porosity was more than 87.9 卤1.2. The stress-strain curves of different layers of the scaffold showed that, under the action of small stress, the pore size of the scaffold was more than 87.9 卤1.2. The material shows linear elastic behavior. When the strain continues to increase by 30% and the stress increases uniformly, the stress increases rapidly when the strain is greater than 40%. The results of TGA test show that there is no porosity agent and solvent residue in the scaffold. To sum up, the PLA porous scaffold was prepared by SC/VV/PL method, which inherits all the advantages of the traditional SC/PL method, and overcomes the disadvantage that SC/PL method is only suitable for the preparation of thin layer scaffolds with thick 2~3mm thickness. In addition, SC-V / V / PL method has the advantages of faster and more thorough volatilization of solvent in vacuum, and suitable for preparing various kinds of scaffolds.
【学位授予单位】：湖北工业大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

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