Hydrogen peroxide (H₂O₂) plays vital roles in oxidative stress and signal transduction in living organisms, and its abnormal levels could be linked to many diseases. Despite numerous efforts spent, it is still urgent and of high importance to develop better H₂O₂ probes with good selectivity, high sensitivity and low backgrounds. To this end, a novel boron dipyrromethene (BODIPY)-based fluorescent probe with an electron-withdrawing methylenemalononitrile at the meso position has been rationally designed, successfully synthesized and investigated for detection of H₂O₂ in aqueous solutions and living cells, which exhibited high selectivity and sensitivity, fluorescent “turn-on” phenomenon at 540 nm, and ratiometric changes from 506 to 540 nm. Upon exposure to H₂O₂, a strong fluorescent emission at 540 nm appeared and the corresponding quantum yields changed from 0.009 to 0.13. The detection limit towards H₂O₂ was calculated to be 31 nM by the linear fluorescence change at 540 nm in the H₂O₂-concentration ranging from 2 to 10 μM. This probe was applicable in a pH range from 6 to 10. Meanwhile, the sensing mechanism was also confirmed by the ¹H NMR and mass spectrometry, suggesting that the above changes might be ascribed to the quick addition and oxidization of the double bond. Furthermore, confocal imaging results also showed great enhancement of intracellular fluorescence upon exposure to H₂O₂ and PMA in RAW264.7 cells, unambiguously confirming its great potentials as a fluorescent probe for highly sensitive detection of both exogenous and endogenous H₂O₂ in living cells.

过氧化氢 (H ₂ O ₂ ) 在生物体的氧化应激和信号转导中发挥着重要作用，其异常水平可能与许多疾病有关。尽管付出了许多努力，但开发具有良好选择性、高灵敏度和低背景的更好的 H ₂ O _{2探针仍然是紧迫和重要的。}为此，合理设计、成功合成了一种新型的基于硼二吡咯亚甲基（BODIPY）的荧光探针，该荧光探针在中间位具有吸电子亚甲基丙二腈，并用于H ₂ O _{2的检测。}在水溶液和活细胞中，表现出高选择性和灵敏度，在 540 nm 处有荧光“开启”现象，在 506 至 540 nm 处有比例变化。暴露于 H ₂ O ₂后，在 540 nm 处出现强荧光发射，相应的量子产率从 0.009 变为 0.13。通过在2 至 10 μM 范围内的 H ₂ O ₂浓度下在 540 nm 处的线性荧光变化，计算出对 H ₂ O ₂的检测限为 31 nM。该探针适用于 6 至 10 的 pH 值范围。同时，传感机制也被¹H NMR和质谱，表明上述变化可能归因于双键的快速加成和氧化。此外，共聚焦成像结果还显示，在 RAW264.7 细胞中，暴露于 H ₂ O ₂和 PMA 后，细胞内荧光显着增强，明确证实了其作为荧光探针的巨大潜力，可用于高灵敏度检测外源性和内源性 H ₂ O ₂。活细胞。