This study aimed to develop a novel and practical fluorescent method for GSH detection in complex biological samples. To this end, a series of coumarin-based fluorescent probes was designed and synthesized using various aliphatic halogens as the sensing group. By using a new evaluation method of GSH/Cys/Hcy coexisting conditions, the probe with chloropropionate (CBF3) showed a high selectivity, excellent sensitivity, good stability for GSH detection. The reaction mechanism is proposed as nucleophilic substitution/cyclization and intramolecular charge transfer (ICT), which was confirmed by LC-MS and NMR analysis, as well as density functional theory calculations. In addition, CBF3 was demonstrated to be competent not only for the quantitative detection of GSH in real serum samples, but also for sensing GSH changes in different oxidative stress models in living cells and nematodes. This study showed a practical strategy for constructing GSH-specific fluorescent probes, and provided a sensitive tool for real-time sensing of GSH in real biological samples. The findings would greatly facilitate further investigations on GSH-associated clinical diagnosis and biomedical studies.

中文翻译：

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一种检测生物样品中谷胱甘肽的新型荧光探针的设计与应用

本研究旨在开发一种新颖实用的荧光方法来检测复杂生物样品中的 GSH。为此，以各种脂肪族卤素为传感基团，设计并合成了一系列基于香豆素的荧光探针。通过采用新的GSH/Cys/Hcy共存条件评价方法，氯丙酸酯(CBF3)探针对GSH检测表现出高选择性、优异的灵敏度和良好的稳定性。反应机理被提出为亲核取代/环化和分子内电荷转移 (ICT)，这通过 LC-MS 和 NMR 分析以及密度泛函理论计算得到证实。此外，CBF3 被证明不仅能够定量检测真实血清样品中的 GSH，还可用于感知活细胞和线虫中不同氧化应激模型中 GSH 的变化。该研究展示了一种构建GSH特异性荧光探针的实用策略，并为实时检测真实生物样品中的GSH提供了一种灵敏的工具。这些发现将极大地促进对 GSH 相关临床诊断和生物医学研究的进一步调查。