Implantation of a scaffold into the body in a safe and convenient manner remains a challenge in the repair of patient bone defect. In the present study, a strategy for fabrication of the redox-sensitive nanofibers with a core–shell structure that can deliver the growth factors in a tunable manner is presented. Poly(ethylene oxide) (PEO) and bone morphogenetic protein 2 (BMP-2) forms the inner core region, and a mixture of poly(epsilon-caprolactone) (PCL) and redox-responsive c-6A PEG–PCL nanogel with −S–S– bond forms the outer shell. The redox-sensitive shell of the nanofibers can respond the change of the GSH (glutathione) concentration and thus regulate the BMP-2 release behavior in vitro and in vivo. In vitro cytotoxicity results indicated that the redox-sensitive nanofiber had good osteoinduction. The in vivo results demonstrated that the nanofibers exhibited a capacity of prompting new bone generation in the bone defect. Therefore, the redox-responsive nanofiber in the present study may be of great potential for application in bone reconstruction.

中文翻译：

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设计用于骨重建的氧化还原敏感药物负载纳米纤维。

以安全和方便的方式将支架植入体内仍然是修复患者骨缺损的挑战。在本研究中，提出了一种制造氧化还原敏感纳米纤维的策略，该纤维具有核-壳结构，可以以可调的方式传递生长因子。聚环氧乙烷（PEO）和骨形态发生蛋白2（BMP-2）形成内核区域，以及聚（ε-己内酯）（PCL）和氧化还原响应性c-6A PEG-PCL纳米凝胶的混合物，其- S–S–键形成外壳。纳米纤维的氧化还原敏感壳可以响应GSH（谷胱甘肽）浓度的变化，从而在体内外调节BMP-2的释放行为。体外细胞毒性结果表明，对氧化还原敏感的纳米纤维具有良好的骨诱导作用。体内结果表明，纳米纤维表现出促进骨缺损中新的骨生成的能力。因此，本研究中的氧化还原反应性纳米纤维在骨重建中可能具有巨大的潜力。