具有不同拓扑结构的海藻酸钠-明胶复合水凝胶的3D打印制备及其性能

Preparation and properties of sodium alginate-gelatin composite hydrogels with different topological structures by 3D printing

模拟皮肤真皮胶原蛋白纤维多角度排列的结构−3D打印相邻两层纤维夹角分别为45°、60°和90°三种拓扑结构的海藻酸钠(SA)-明胶(GEL)复合支架,研究拓扑结构对水凝胶支架性能的影响。SEM表征支架的微观结构,测量各组支架的含水率、孔隙率、力学性能、溶胀率和体外降解率,FTIR测试SA、GEL和复合水凝胶的官能团,细胞计数试剂盒(CCK-8)和免疫荧光染色检测支架对成纤维细胞(HFb)的毒性与支架的生物相容性进行表征。结果表明:各组支架拓扑结构清晰;FTIR图谱中吸收峰的相对位置提供了支架材料的化学结构;三组支架含水率和孔隙率均大于80%;45°、60°和90°支架的压缩弹性模量分别为(3.57±0.14)kPa、(3.18±0.31)kPa和(2.03±0.29)kPa。CCK-8结果表明,三组支架上细胞活性均保持在无支架对照组的90%以上。微丝和核染色结果显示,HFb接种第1天时在45°支架上的铺展优于其他两组,随着时间增加,HFb在三组支架上明显增殖,表明支架具有良好的细胞相容性。本文设计与表征了不同拓扑结构SA-GEL支架的性能,并为后续组织工程真皮的构建及在三维基质上分析HFb集体迁移的研究提供了重要基础。

In this paper,the structure of skin dermal collagen fibers were simulated,and the sodium alginate(SA)-gelatin(GEL)composite scaffold with three topological angles of 45°,60°and 90°were 3D printed to study the effect of topology on the performance of the hydrogel scaffold,respectively.SEM were used to characterize the microstructure of the scaffolds.The water content,porosity,mechanical properties,swelling ratio and in vitro degradation ratio of each group of scaffolds were measured.FTIR were used to test the functional groups of SA,GEL and composite hydrogel.Cell counting kit-8(CCK-8)reagent and immunofluorescence staining were used to test the toxicity of the scaffolds to human dermal fibroblasts(HFb)and the biocompatibility of scaffolds.The results show that the topology of each group is clear.The relative position of the absorption peak in the FTIR spectrum provides the chemical structure of the scaffold material.The water content and porosity of the three groups are all greater than 80%.The compressive elastic modulus of the 45°,60°and 90°scaffolds are(3.57±0.14)kPa,(3.18±0.31)kPa and(2.03±0.29)kPa,respectively.CCK-8 results show that the cell activity on three groups is maintained at more than 90%of control group without scaffolds.The results of microfilament and nuclear staining show that the spread of HFb on the 45°scaffold on the first day of inoculation is better than that of the other two groups,HFb proliferates significantly on the three groups of scaffolds with the increase of time,indicating that the scaffold has good cytocompatibility.This paper designs and characterizes the performance of SA-GEL scaffolds with different topologies,and provides an important foundation for the construction of subsequent tissue engineering dermis and the analysis of HFb collective migration on a three dimensional matrix.