Attractive benzothiazole-based fluorescence probe for the highly efficient detection of hydrogen peroxide

In current work, one novel benzothiazole-based fluorescent chemosensor (TZ-BO) with ESIPT luminescence mechanism was designed for the detection of hydrogen peroxide (H₂O₂) as typical reactive oxygen species (ROS). The boronate catenary in our designed probe molecule TZ-BO is both the blocking group of ESIPT and the reactive group of H₂O₂. The synthesized probe TZ-BO has the advantages of large Stokes shift, high sensitivity, good selectivity, and fast reaction speed to H₂O₂. The ability of the probe to detect H₂O₂ in aqueous media and exogenous H₂O₂ in cells by fluorescence signal was investigated. The experimental results manifested that probe TZ-BO is able to sensitively detect H₂O₂ using a fluorescence method in an excellent linear range of H₂O₂ concentration from 0 to 60 μM (R² = 0.994). The detection limit was determined as 1.0 × 10^-6 M. Most importantly, the probe TZ-BO with highly low cytotoxicity can effectively detect exogenous H₂O₂ in HeLa cells. This probe provides a promising tool for monitoring the real concentration level of H₂O₂ in related physiological and pathological researches.