Fernández Daniel, Guerra Montserrat, Lisoni Judit G, Hoffmann Thomas, Araya-Hermosilla Rodrigo, Shibue Toshimichi, Nishide Hiroyuki, Moreno-Villoslada Ignacio, Flores Mario E
Instituto de Ciencias Químicas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia 5090000, Chile.
Instituto de Anatomía, Histología y Patología, Facultad de Medicina, Universidad Austral de Chile, Valdivia 5090000, Chile.
Polymers (Basel). 2019 Oct 8;11(10):1621. doi: 10.3390/polym11101621.
In this work, we design and produce micron-sized fiber mats by blending poly(-caprolactone) (PCL) with small amounts of block copolymers poly(ethylene oxide)poly(-caprolactone) (PEO--PCL) using electrospinning. Three different PEO--PCL block copolymers, with different molecular weights of PEO and PCL, were synthesized by ring opening polymerization of ε-caprolactone using PEO as initiator and stannous octoate as catalyst. The polymer blends were prepared by homogenous solvent mixing using dichloromethane for further electrospinning procedures. After electrospinning, it was found that the addition to PCL of the different block copolymers produced micron-fibers with smaller width, equal or higher hydrophilicity, lower Young modulus, and rougher surfaces, as compared with micron-fibers obtained only with PCL. Neural stem progenitor cells (NSPC), isolated from rat brains and grown as neurospheres, were cultured on the fibrous materials. Immunofluorescence assays showed that the NSPC are able to survive and even differentiate into astrocytes and neurons on the synthetic fibrous materials without any growth factor and using the fibers as guidance. Disassembling of the cells from the NSPC and acquisition of cell specific molecular markers and morphology progressed faster in the presence of the block copolymers, which suggests the role of the hydrophilic character and porous topology of the fiber mats.
在本研究中，我们通过静电纺丝将聚（ε-己内酯）（PCL）与少量嵌段共聚物聚（环氧乙烷）-聚（ε-己内酯）（PEO-PCL）混合，设计并制备了微米级纤维垫。以PEO为引发剂、辛酸亚锡为催化剂，通过ε-己内酯的开环聚合反应合成了三种不同分子量的PEO-PCL嵌段共聚物。聚合物共混物通过使用二氯甲烷进行均相溶剂混合来制备，以用于进一步的静电纺丝过程。静电纺丝后发现，与仅由PCL获得的微米纤维相比，添加不同的嵌段共聚物到PCL中可产生宽度更小、亲水性相同或更高、杨氏模量更低且表面更粗糙的微米纤维。从大鼠大脑中分离并培养成神经球的神经干祖细胞（NSPC），在这些纤维材料上进行培养。免疫荧光分析表明，NSPC能够在合成纤维材料上存活，甚至在没有任何生长因子且以纤维为导向的情况下分化为星形胶质细胞和神经元。在嵌段共聚物存在的情况下，NSPC细胞的解离以及细胞特异性分子标记物的获得和形态变化进展得更快，这表明了纤维垫的亲水性特征和多孔拓扑结构的作用。
