Hydrogen sulfide (H₂S) is believed to play an important role in maintaining cellular redox homeostasis and avoiding oxidative damage caused by abnormally raised ROS levels. Highly selective and sensitive fluorescent probes for the detection and imaging of endogenous H₂S in living cells over other biological thiols are desirable. Herein, we developed a mitochondria-targeted fluorescent probe L, a thioxanthene-benzo[e]indolium derivative, for the discrimination of H₂S from other chemically similar biothiols. Based on the nucleophilic addition of H₂S and the charged electron-deficient CN double bond within the benzo[e]indolium moiety, the generation of L-HS with a shortened π-conjugated system led to significant spectral changes in the visible region. Importantly, the probe L with mitochondria-targeting ability has been successfully used for imaging the endogenous H₂S biosynthesized from Cys and GSH and in cellular antioxidant stress.

中文翻译：

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线粒体靶向荧光探针在细胞抗氧化应激中内源性硫化氢成像

硫化氢（H ₂ S）被认为在维持细胞氧化还原稳态和避免由ROS水平异常升高引起的氧化损伤中起重要作用。内源H的检测和成像高选择性和灵敏的荧光探针₂ S IN活超过其它生物细胞硫醇类是所希望的。在这里，我们开发了一种针对线粒体的荧光探针L，一种噻吨蒽-苯并[ e ]吲哚鎓衍生物，用于区分H ₂ S与其他化学相似的生物硫醇。基于H ₂ S的亲核加成和苯并[ e]中带电的缺电子C N双键在吲哚鎓部分，具有缩短的π-共轭体系的L-HS的产生导致可见光区域的显着光谱变化。重要的是，具有线粒体靶向能力的探针L已成功用于成像从Cys和GSH生物合成的内源性H ₂ S以及细胞抗氧化应激。