A simple boronic acid-based fluorescent probe for selective detection of hydrogen peroxide in solutions and living cells

An approach of high sensitivity and selectivity for hydrogen peroxide (H2O2) detection is highly demanded due to its important roles in regulating diverse biological process. In this work, we introduced an easily synthesized fluorescent turn off probe, BNBD. It is designed based on the core structure of 4-chloro-7-nitrobenzofurazan as a fluorophore and incorporated with a specific H2O2-reactive group, aryl boronate, for sensitive and selective detection of H2O2 . We demonstrated its selectivity by incubating the probe with other types of ROS, and measured the limit of detection of BNBD as 1.8 nM. BNBD is also conducive to H2O2 detection at physiological conditions. We thus applied it to detect both exogenous and endogenous changes of H2O2 in living cells by confocal microscopy, supporting its future applications to selectively monitor H2O2 levels and identify H2O2 related physiological or pathological responses from live cells or tissues in the near future.