A Benzil- and BODIPY-Based Turn-On Fluorescent Probe for Detection of Hydrogen Peroxide.

Faced with rising threats of terrorism, environmental and health risks, achieving sensitive and selective detection of peroxide-based explosives (PEs) has become a global focus. In this study, a turn-on fluorescent probe (BOD) based on benzil (HO-recognition element) and 4,4-difluoro-4-bora-3,4-diaza--indacene (BODIPY) derivative (fluorophore) was developed to sensitively and specifically detect hydrogen peroxide (HO). The synthesized BOD had a very weak fluorescence due to intramolecular donor-excited photo-induced electron transfer (-PET) effect; however, it could emit a strong fluorescence since HO selectively oxidized the benzil moiety and released free BODIPY fluorophore (BOD-COOH). As a result, the proposed BOD detected HO in linear detection ranged from 25 to 125 µM with a detection limit of 4.41 µM. Meanwhile, the proposed BOD showed good selectivity toward HO, which is not affected by other common reactive oxygen species (ROS) and ions from explosive residues. In addition, a blue shift from 508 to 498 nm was observed in the absorption spectra upon addition of HO. More importantly, the BOD was successfully applied for rapid detection of HO vapor with good sensitivity (down to 7 ppb), which holds great potential for practical use in public safety, forensic analysis and environmental monitoring.