Nitric oxide (NO) is an important signaling molecule involved in various physiological and pathological processes. The effects of NO depend on its concentration, and the spatial and temporal constraints of the cell microenvironment. Meanwhile, NO can react with some biomolecules such as biothiols, leading to a short biological lifetime. Thus, it is very crucial to establish a real-time visualization method for monitoring NO levels. In this work, we have developed a fluorescent probe, RBA, for NO, with a 3-extended BODIPY as a fluorophore and a secondary amine as the active site. The probe RBA can quickly sense NO (∼10 s) in aerobic solutions to generate a fluorescent N-nitrosamine (RBA-NO, Φ_f = 0.87) due to blocking of the photoinduced electron transfer (PET) process from the secondary amine to the BODIPY core. This sensing reaction displays high sensitivity (LOD = 10 nM) and high selectivity for NO over relevant analytes except some reducing reagents including biothiols, and a remarkable interference effect is observed ascribed to a competitive reaction with biothiols. Furthermore, the exo- and endogenous detection of NO in live cells and zebra fish was achieved, and it was demonstrated that glutathione (GSH) weakens drastically the fluorescence response by cell-imaging experiments. These results imply that the colorimetric and fluorescence response of the chemosensor for NO depends on the levels of both NO and GSH in environments.

中文翻译：

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基于BODIPY的荧光探针在活细胞中快速灵敏地检测一氧化氮：谷胱甘肽效应

一氧化氮（NO）是涉及各种生理和病理过程的重要信号分子。NO的影响取决于其浓度以及细胞微环境的时空限制。同时，NO可以与某些生物分子（例如生物硫醇）反应，从而缩短生物寿命。因此，建立实时的可视化方法来监测NO水平非常关键。在这项工作中，我们开发了一种用于NO的荧光探针RBA，该探针具有3个扩展的BODIPY作为荧光团和仲胺作为活性位点。探针RBA可以快速在有氧溶液感测NO（〜10个或多个），以生成荧光Ñ -nitrosamine（RBA-NO，Φ _˚F= 0.87）是由于从仲胺到BODIPY核的光致电子转移（PET）过程受阻。除了某些还原剂（包括生物硫醇）外，该传感反应对相关分析物显示出高灵敏度（LOD = 10 nM）和对NO的高选择性，并且观察到显着的干扰作用归因于与生物硫醇的竞争性反应。此外，实现了活细胞和斑马鱼中NO的外源和内源检测，并且通过细胞成像实验证明了谷胱甘肽（GSH）大大减弱了荧光反应。这些结果表明，化学传感器对NO的比色和荧光响应取决于环境中NO和GSH的水平。