Dual Mechanism of an Intramolecular Charge Transfer (ICT)–FRET‐Based Fluorescent Probe for the Selective Detection of Hydrogen Peroxide

A dual‐mechanism intramolecular charge transfer (ICT)–FRET fluorescent probe for the selective detection of H 2 O 2 in living cells has been designed and synthesized. This probe used a coumarin–naphthalimide hybrid as the FRET platform and a boronate moiety as the recognition group. Upon the addition of H 2 O 2 , the probe exhibited a redshifted (73 nm) fluorescence emission, and the ratio of fluorescence intensities at λ =558 and 485 nm ( F 558 / F 485 ) shifted notably (up to 100‐fold). Moreover, there was a good linearity ( R 2 =0.9911) between the ratio and concentration of H 2 O 2 in the range of 0 to 60 μ m , with a limit of detection of 0.28 μ m (signal to noise ratio (S/N)=3). This probe could also detect enzymatically generated H 2 O 2 . Importantly, it could be used to visualize endogenous H 2 O 2 produced by stimulation from epidermal growth factor.