Borah Rajiv, Ingavle Ganesh C, Sandeman Susan R, Kumar Ashok, Mikhalovsky Sergey V
Materials Research Laboratory, Department of Physics, Tezpur University, Tezpur 784028, India.
Biomaterials and Medical Devices Research Group, School of Pharmacy and Biomolecular Sciences, Huxley Building, University of Brighton, Brighton BN2 4GJ, United Kingdom.
ACS Biomater Sci Eng. 2018 Sep 10;4(9):3327-3346. doi: 10.1021/acsbiomaterials.8b00624. Epub 2018 Aug 29.
In the present study, a conducting polymer, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) along with a biodegradable polymer poly(ε-caprolactone) (PCL) was used to prepare an electrically conductive, biocompatible, bioactive, and biodegradable nanofibrous scaffold for possible use in neural tissue engineering applications. Core-sheath electrospun nanofibers of PCL as the core and MEH-PPV as the sheath, were surface-functionalized with (3-aminopropyl) triethoxysilane (APTES) and 1,6-hexanediamine to obtain amine-functionalized surface to facilitate cell-biomaterial interactions with the aim of replacing the costly biomolecules such as collagen, fibronectin, laminin, and arginyl-glycyl-aspartic acid (RGD) peptide for surface modification. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the formation of core-sheath morphology of the electrospun nanofibers, whereas Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) revealed successful incorporation of amine functionality after surface functionalization. Adhesion, spreading, and proliferation of 3T3 fibroblasts were enhanced on the surface-functionalized electrospun meshes, whereas the neuronal model rat pheochromocytoma 12 (PC12) cells also adhered and differentiated into sympathetic neurons on these meshes. Under a constant electric field of 500 mV for 2 h/day for 3 consecutive days, the PC12 cells displayed remarkable improvement in the neurite formation and outgrowth on the surface-functionalized meshes that was comparable to those on the collagen-coated meshes under no electrical signal. Electrical stimulation studies further demonstrated that electrically stimulated PC12 cells cultured on collagen I coated meshes yielded more and longer neurites than those of the unstimulated cells on the same scaffolds. The enhanced neurite growth and differentiation suggest the potential use of these scaffolds for neural tissue engineering applications.
在本研究中，一种导电聚合物聚2-甲氧基-5-(2-乙基己氧基)-1,4-亚苯基乙烯撑与一种可生物降解聚合物聚(ε-己内酯)(PCL)一起用于制备一种导电、生物相容、生物活性和可生物降解的纳米纤维支架，可能用于神经组织工程应用。以PCL为核、MEH-PPV为壳的核壳结构电纺纳米纤维用(3-氨丙基)三乙氧基硅烷(APTES)和1,6-己二胺进行表面功能化，以获得胺功能化表面，促进细胞与生物材料的相互作用，目的是替代用于表面修饰的昂贵生物分子，如胶原蛋白、纤连蛋白、层粘连蛋白和精氨酰-甘氨酰-天冬氨酸(RGD)肽。扫描电子显微镜(SEM)和透射电子显微镜(TEM)证实了电纺纳米纤维核壳结构的形成，而傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)显示表面功能化后成功引入了胺功能。表面功能化的电纺网片上3T3成纤维细胞的黏附、铺展和增殖增强，而神经元模型大鼠嗜铬细胞瘤12(PC12)细胞也在这些网片上黏附并分化为交感神经元。在500 mV的恒定电场下，每天2 h，连续3天，PC12细胞在表面功能化网片上的神经突形成和生长有显著改善，与无电信号时胶原包被网片上的情况相当。电刺激研究进一步表明，在I型胶原包被网片上培养的电刺激PC12细胞比在相同支架上未刺激的细胞产生更多更长的神经突。神经突生长和分化的增强表明这些支架在神经组织工程应用中的潜在用途。
