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

Abstract

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.

Keywords: Boronic acid; Fluorescent probe; Hydrogen peroxide; Living cells.