低渗联合冻干技术制备脱细胞神经支架及其力学性能分析

Preparation and biomechanical properties of acellularized nerve scaffold using the technique of hypotonic buffer combined with freeze-drying

目的研究低渗联合冻干技术改良制备的脱细胞神经支架材料的组织学和生物力学特性。方法采用低渗联合冻干技术对传统脱细胞神经支架材料进行改良,脱细胞完成后通过HE染色和扫描电镜观察各组神经组织的组织学结构;利用Mimics软件测定脱细胞神经支架的孔隙率及空隙直径;并采用Endura TEC ELF3200力学仪器测试各组神经的生物力学特性。结果改良组所获得的脱细胞神经的脱细胞效果与传统脱细胞方法组相似,但组织结构更为疏松;传统和改良脱细胞组平均孔隙率分别为34.5%、49.3%,空隙直径分别为11.96、17.61μm;生物力学测试结果表明各组神经的生物力学特性(极限载荷、极限应力、极限应变、断裂功耗等)经检验无统计学差异(P>0.05)。结论低渗联合冻干技术制备的脱细胞神经可作为一种更有利于细胞复合的神经支架材料。

Objective To study the morphology and biomechanical properties of the improved acellularized nerve scaffold using the technique of hypotonic buffer combined with freeze-drying. Methods The traditional acellu- larized nerve scaffold （traditional group） was made to be improved with the technique of hypotonic buffer com- bined with freeze-drying （improved group）. After the acellularization process was completed, the histological structure of nerves in each group was observed by HE staining and scanning electron microscope. The interval porosity and void diameter in each group were measured by Mimics software. The biomechanical properties of nerves in each group were tested by mechanical apparatus （ Endura TEC ELF3200）. Results The acellulariza- tion effect of the improved chemical method with the technique of hypotonic buffer combined with freeze-drying was similar to that of the traditional Hudson method, but the histological structure was more porous in improved group than that in traditional group. The interval porosity of traditional group and improved group were 34.5% and 49.3%, respectively; the void diameter of traditional group and improved group were 11.96 and 17.61μm, re- spectively. Biomechanical testing results showed that there was no statistical difference in ultimate load, ultimate stress, ultimate strain and mechanical work to fracture in each group （ P 〉0.05）. Conclusions The acellularizednerve prepared by hypotonic buffer combined with freeze-drying can be used as a new kind of nerve scaffold ma- terial to make better contribution to cell combination.