三维多孔电磁复合支架构建与理化表征  

Fabrication and Characterization of Three-Dimensional Porous Electromagnetic Composite Scaffolds

作　　者：徐学盖 吴凤新[1] 高爱军 孟洁[1] 温涛 刘健[1] 徐樑华[2] 许海燕[1] Xu Xuegai;Wu Fengxin;Gao Aijun;Meng Jie;Wen Tao;Liu Jian;Xu Lianghua;Xu Haiyan(Institute of Basic Medical Sciences,Chinese Academy of Medical Sciences&Peking Union Medical College,Beijing 100005,China;Key Lahoratory of Carbon Fiber and Functional Polymers,Ministry of Education,Beijing University of Chemical Technology,Beijing 100029,China)

机构地区：[1]中国医学科学院基础医学研究所,北京协和医学院基础学院,北京100005 [2]北京化工大学碳纤维及功能高分子教育部重点实验室,北京100029

出　　处：《中国生物医学工程学报》2019年第4期447-454,共8页Chinese Journal of Biomedical Engineering

基　　金：中国医学科学院医学与健康科技创新工程项目(CIFMS 2016-I2M-3-004)

摘　　要：模拟心肌细胞外基质(ECM)的组织结构和电生理特性,构建具有导电性和超顺磁响应性的三维多孔纳米纤维复合材料支架,为细胞黏附、增殖和分化提供有利的微环境。以明胶为壳层、聚乳酸为芯层,并在各层中引入四氧化三铁纳米颗粒,采用共轴静电纺丝技术,制备纳米纤维薄膜;将其粉碎并与碳纤维混合,经冷冻干燥和交联处理,得到三维多孔支架。用扫描电镜和透射电镜观察支架形貌及结构,用四探针仪测定支架的电导率,用振动样品磁强计测量支架磁滞回线,用万能材料试验机检测支架材料的压缩应力-应变曲线;根据质量和体积计算支架密度,根据支架吸水前后质量计算吸水率。用CCK-8和Western Blot,分析细胞在支架上的活性及功能。支架内部呈多孔蜂窝结构,孔隙间相互贯通;当碳纤维含量为0、1、3、5 mg/mL时,支架密度分别为73.07、72.56、65.88、63.34 mg/cm^3,吸水率分别为1 164.60%、1 186.48%、1 284.84%、1 323.66%;电导率分别为0、0.008 8、0.246 7、2.662 5 s/m,最大磁饱和强度分别为3.68、3.15、2.45、2.90 emu/g,抗压缩能力也相应提高。上述复合材料支架能够显著促进心肌细胞成熟相关蛋白Cx43和RhoA的表达,诱导心肌细胞向成熟分化。三维多孔电磁复合支架同时具有超顺磁性和导电性,微观上具有纳米纤维网络和多孔结构,并通过碳纤维的复合,使力学性能得到显著提高,支持心肌细胞生长并促进其成熟。Objective:To mimic the tissue structure and physiological function of extracellular matrix(ECM)to fabricate electromagnetic nanofibrous scaffolds that are favorable for cell adhesion,proliferation and differentiation.Nanofibrous films were fabricated by coaxial electrospinning with gelatin as shell layer and polylactic acid(PLA)as core layer;meanwhile,magnetic nanoparticles(MNP)were added into the gelatin and PLA.The obtained nanofibrous films were pulverized and blended with carbon fiber(CF),followed by freeze-drying and crosslinking treatment to obtain three-dimensional(3 D)porous scaffolds.The morphology and structure of the scaffolds were observed by scanning electron microscope(SEM)and transmission electron microscope(TEM).The hysteresis loop was measured by vibrating sample magnetometer,the conductivity was measured using four point probe,and compression tests were carried out by universal material testing machine.The density and water absorption were also measured.CCK-8 and Western Blot were used to analyze the viability and function of the cells on the scaffolds.The scaffolds showed porous honeycomb microstructure,the pores were perforated with each other.When CF content was 0,1,3 and 5 mg/mL,the density of scaffolds was 73.07,72.56,65.88 and 63.34 mg/cm^3,the water absorption was 1164.60%,1186.48%,1284.835%and 1323.66%,the conductivity was 0,0.0088,0.2467 and 2.6625 s/m,and the saturated magnetization strength was 3.68,3.15,2.45 and 2.90 emu/g,respectively.The scaffolds up-regulated the expression of Cx43 and RhoA,as well as supported the growth of cardiomyocytes.The 3 D porous electromagnetic composite scaffolds had both superparamagnetism and conductivity,the mechanical property was significantly improved by CF.The scaffolds supported growth and promoted the maturation of cardiomyocytes.

关 键 词：电磁复合支架 细胞外基质 碳纤维 心肌细胞 

分 类 号：R318[医药卫生—生物医学工程]