An ICT-Based Coumarin Fluorescent Probe for the Detection of Hydrazine and Its Application in Environmental Water Samples and Organisms

As an inorganic small molecule pollutant, the toxicity and potential carcinogenicity of hydrazine (N2H4) are of increasing concern. In this work, A water-soluble fluorescent probe (OCYB) based on the intramolecular charge transfer (ICT) mechanism for the detection of hydrazine was designed and synthesized. Taking the advantage of 4-bromobutyryl as the recognition group, the high selectivity of OCYB to N2H4 was confirmed by steady-state fluorescence spectroscopy. The limit of detection (LOD) was calculated to be 78 nM in the DMSO-HEPES (pH 7.4) system. The detection mechanism was verified by NMR, HRMS and density functional theory (DFT) calculations. In addition, OCYB exhibits strong anti-interference ability and an "Off-On" fluorescence enhancement effect. Importantly, OCYB can be used to effectively monitor the fluorescence distribution of N2H4 in environmental water samples and organisms.