A mitochondria-targeted colorimetric and ratiometric fluorescent probe for hydrogen peroxide with a large emission shift and bio-imaging in living cells

A novel mitochondria-targeted fluorescent probe compound 1 for H2O2 has constructed based on a coumarin as the fluorophore and a boronate moiety as the reaction site, which showed colorimetric and ratiometric fluorescence dual response to H2O2. This probe displayed a large blue-shifted in emission wavelength (105 nm) with two well-resolved emission bands toward hydrogen peroxide. The compound 1 can be quantitative, good selective and sensitive recognition to H2O2 with low detection limit (10 nM). The sensing mechanism was confirmed by H NMR and HRMS spectroscopy. The mechanism regarding the optical responses of the compound 1 toward H2O2 was also determined by density function theory (DFT) calculations. Moreover, the probe could be used for determining H2O2 in living cells by ratiometric fluorescence imaging with excellent mitochondrial targeting.