A bioreduction-responsive nanographene oxide (NGO) based drug delivery system (DDS) for chemotherapy with a disulfide linker as a glutathione-responsive switch is designed and prepared in a facile way, which can only be activated to release original water-insoluble anticancer drugs in cancer cells. For better biocompatibility and more functionalization, this DDS was constructed through a promising platform (PEG-NGO-SH), which is based on dual-functionalized NGO with six-armed poly(ethylene glycol) on the edge and thiol groups on the basal plane. After systematic experiments, this DDS was found to exhibit a suitable lateral size (180 nm), high drug loading ratio (∼20 wt%), selective release (∼90% in 10 mM GSH), bioavailability and significant difference in cytotoxicity to normal (293T) and cancer (A549) cells. The efficacy of this DDS was proved by the effective in vitro release behavior in high GSH level medium and the significant difference in cytotoxicity against A549 and 293T cells. Thus, it was obviously verified that this bioreduction-responsive DDS triggered by GSH and its construction method using a disulfide linker as a switch on dual-functionalized NGO show potency toward tumor-targeted therapy.

中文翻译：

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带有合适的谷胱甘肽响应开关的简便的PEG /硫醇官能化纳米氧化烯载体

以二硫键作为谷胱甘肽反应开关的化学还原反应生物纳米氧化烯（NGO）为基础的药物输送系统（DDS）的设计和制备，只能通过激活才能释放出原始的水不溶性抗癌药物在癌细胞中。为了获得更好的生物相容性和更多的功能化，该DDS是通过一个有前途的平台（PEG-NGO-SH）构建的，该平台基于双功能化NGO，边缘具有六臂聚乙二醇，并且基平面具有巯基。经过系统的实验后，发现该DDS具有合适的横向尺寸（180 nm），高载药率（〜20 wt％），选择性释放（在10 mM GSH中为〜90％），生物利用度以及与正常细胞毒性的显着差异（293T）和癌细胞（A549）。高GSH水平培养基中的体外释放行为以及对A549和293T细胞的细胞毒性的显着差异。因此，显然证实了由GSH触发的这种生物还原反应性DDS及其使用二硫键作为双功能NGO开关的构建方法显示出对肿瘤靶向治疗的潜力。