高仿真组织工程神经支架制备工艺的参数优化

目的：对直接影响神经支架微观结构的关键因素进行分析,以确定制备不同孔径仿真支架的制备工艺。方法：用前期开发的神经支架制备工艺,应用不同浓度的醋酸浓度和冷淋速度制备仿真神经支架,以扫描电镜观察神经支架结构特征,以确定醋酸浓度和冷淋速度对神经支架内部结构的影响。结果：醋酸浓度和冷淋速度对神经支架内部结构具有重要影响。醋酸浓度为0mg/ml时,无法制备定向结构的神经支架,当醋酸浓度为1mg/ml、2mg/ml、3mg/ml和4mg/ml时,可制备轴定向仿真支架,并且神经支架的孔径随醋酸浓度增大而增大;当冷淋速度为1×10-5m/s、2×10-5m/s和5×10-5m/s时,所制备的仿真支架内部均呈明显的轴向微管结构,其中冷淋速度为2×10-5m/s时,其轴向微管结构排列最为有序、规律。当速度为1×10-6m/s,2×10-6m/s,5×10-6m/s以及1×10-4m/s时,所制备的材料内部微管结构走向无明显规律。结论：醋酸浓度和冷淋速度是影响神经支架内部结构的两个关键因素,通过改变醋酸浓度和冷淋速度可制备不同孔径的仿真神经支架。

Parameter Optimization of the Fabrication Technique for Highly Bionic Tissue Engineering Nerve Scaffold

Objective：To investigate the factors which influence the micro-structural characteristics of the highly bionic nerve scaffold,and to determine the technology for establishing bionic nerve scaffold with different micro-structural characteristics.Methods：Nerve scaffolds with different micro-structural characteristics were fabricated with varied doses of acetic acid and a series of freezing velocities.Scanning electron microscopy was used to detect the micro-structural characteristics.The effects of acetic acid concentration and freezing velocities on the structural appearance of the scaffolds were determined.Results：The concentration of the acetic acid and freezing velocities had effect on the micro-structural characteristics of the nerve scaffold.Scaffold with longitudinal pores could be fabri-cated in the presence of acetic acid（1 mg/ml,2 mg/ml,3 mg/ml and 4 mg/ml,except 0mg/ml）,and the pore size increased with the increasing of the acetic acid concentration.In addition,highly bionic nerve scaffold could be made when the freezing velocities were maintained at 1×10-5m/s,2×10-5m/s and 5×10-5m/s,of which the most homogeneous longitudinal pores were achieved by velocity at 2×10-5m/s.When the velocity was maintained at 1×10-6m/s,2×10-6m/s,5×10-6m/s and 1×10-4m/s,the scaffold showed no longitudinal pores.Conclusion：Acetic acid concentration and freezing velocities were two key factors determining the micro-structural characteristics of the highly bionic nerve scaffold.Scaffolds with different micro-structural appearances can be fabricated through changing the acetic acid concentration and freezing velocities.