多材料3D打印微管阵列神经支架研究

Study on Multi-Material 3D Printing of Neural Scaffold with Multichannel Characteristics

针对外周神经修复中使用的多通道神经支架加工困难的问题,提出了多材料3D打印技术制备微管阵列甲基丙烯酸酐化明胶(GelMA)神经支架的方法。通过多喷头3D打印技术实现了GelMA材料和明胶材料的多材料精密挤出成型,基于成型过程中明胶材料低温凝胶和升温溶芯工艺获得了高密度微管阵列结构,对最终成型的GelMA神经支架的微管直径、微管间距、孔隙率和力学性能等关键参数进行了评价。研究结果表明:微管直径和间距尺寸的制造误差分别为2.4%和0.3%。随GelMA浓度的增加支架力学性能呈增强的趋势,支架孔隙率呈逐渐降低的趋势。当GelMA浓度为5%和7%时,支架孔隙率在90%以上。综合支架的营养物质扩散、制造误差和力学性能,浓度为7%的GelMA微管阵列神经支架有望满足外周神经再生的需求。

In view of the difficulty of processing the multi-channel nerve scaffold used in peripheral nerve regeneration,a method of manufacturing the multichannel nerve scaffold with gelatin methacrylate(GelMA)using multi-material 3D printing technology was proposed.Through multi-nozzle precise extrusion molding of GelMA and gelatin by 3D printing technology,high-density multichannel structure was obtained based on low-temperature support and temperature-rising core melting process of gelatin.The key physical parameters of peripheral nerve regeneration including micro-tube diameter,micro-tube spacing,porosity and mechanical property were systematically evaluated.The research results show that the manufacturing errors of the micro-tube diameter and the micro-tube spacing are 2.4%and 0.3%,respectively.With the increase of GelMA concentration,the mechanical property of the scaffold shows a trend of enhancement,and the porosity of the scaffold shows a trend of gradual decrease.The porosity of the scaffold gradually decreases with the increase of GelMA concentration.When the concentration of GelMA is 5%and 7%,the porosity of the scaffold is above 90%.Considering the nutrient diffusion,manufacturing errors and mechanical property of the scaffold,nerve scaffold with multichannel characteristics prepared with 7%GelMA is expected to meet the needs of peripheral nerve regeneration.