The endothelialization on the poly (ε-caprolactone) nanofiber has been limited due to its low hydrophilicity. The aim of this study was to immobilize collagen on an ultra-thin poly (ε-caprolactone) nanofiber membrane without altering the nanofiber structure and maintaining the endothelial cell homeostasis on it. We immobilized collagen on the poly (ε-caprolactone) nanofiber using hydrolysis by NaOH treatment and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo-N-hydroxysulfosuccinimide reaction as a cost-effective and stable approach. NaOH was first applied to render the poly (ε-caprolactone) nanofiber hydrophilic. Subsequently, collagen was immobilized on the surface of the poly (ε-caprolactone) nanofibers using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo-N-hydroxysulfosuccinimide. Scanning electron microscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and fluorescence microscopy were used to verify stable collagen immobilization on the surface of the poly (ε-caprolactone) nanofibers and the maintenance of the original structure of poly (ε-caprolactone) nanofibers. Furthermore, human endothelial cells were cultured on the collagen-immobilized poly (ε-caprolactone) nanofiber membrane and expressed tight junction proteins with the increase in transendothelial electrical resistance, which demonstrated the maintenance of the endothelial cell homeostasis on the collagen-immobilized-poly (ε-caprolactone) nanofiber membrane. Thus, we expected that this process would be promising for maintaining cell homeostasis on the ultra-thin poly (ε-caprolactone) nanofiber scaffolds.

中文翻译：

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胶原蛋白固定在超薄纳米纤维膜上以促进体外内皮单层形成。

聚（ε-己内酯）纳米纤维的内皮化由于其低亲水性而受到限制。这项研究的目的是将胶原蛋白固定在超薄聚（ε-己内酯）纳米纤维膜上，而不改变纳米纤维的结构并保持内皮细胞的稳态。我们使用氢氧化钠水解和1-乙基-3-（3-二甲基氨基丙基）碳二亚胺/磺基-N-羟基磺基琥珀酰亚胺反应，将胶原蛋白固定在聚（ε-己内酯）纳米纤维上，作为一种经济高效且稳定的方法。首先使用NaOH使聚（ε-己内酯）纳米纤维具有亲水性。随后，使用1-乙基-3-（3-二甲基氨基丙基）碳二亚胺/磺基-N-羟基磺基琥珀酰亚胺将胶原蛋白固定在聚（ε-己内酯）纳米纤维的表面上。扫描电子显微镜，傅里叶变换红外光谱，透射电子显微镜和荧光显微镜用于验证稳定的胶原蛋白固定在聚（ε-己内酯）纳米纤维的表面上，并保持聚（ε-己内酯）纳米纤维的原始结构。此外，将人内皮细胞培养在胶原蛋白固定的聚（ε-己内酯）纳米纤维膜上并表达紧密连接蛋白，并且跨内皮电阻增加，这证明了胶原蛋白固定的聚（ ε-己内酯）纳米纤维膜。因此，我们预计该过程将有望在超薄聚（ε-己内酯）纳米纤维支架上维持细胞稳态。荧光显微镜技术验证了胶原蛋白在聚（ε-己内酯）纳米纤维表面上的稳定固定，并保持了聚（ε-己内酯）纳米纤维的原始结构。此外，将人内皮细胞培养在胶原蛋白固定的聚（ε-己内酯）纳米纤维膜上并表达紧密连接蛋白，并且跨内皮电阻增加，这证明了胶原蛋白固定的聚（ ε-己内酯）纳米纤维膜。因此，我们预计该过程将有望在超薄聚（ε-己内酯）纳米纤维支架上维持细胞稳态。荧光显微镜技术验证了胶原蛋白在聚（ε-己内酯）纳米纤维表面上的稳定固定，并保持了聚（ε-己内酯）纳米纤维的原始结构。此外，将人内皮细胞培养在胶原蛋白固定的聚（ε-己内酯）纳米纤维膜上并表达紧密连接蛋白，并且跨内皮电阻增加，这证明了胶原蛋白固定的聚（ ε-己内酯）纳米纤维膜。因此，我们预计该过程将有望在超薄聚（ε-己内酯）纳米纤维支架上维持细胞稳态。