A novel flavonol-based colorimetric and turn-on fluorescent probe for rapid determination of hydrazine in real water samples and its bioimaging in vivo and in vitro

Hydrazine is extremely toxic and causes severe harm to human body.Herein,a novel fluorescent probe 4-oxo-2-styryl-4H-chromen-3-yl thiophene-2-carboxylate(FHT)was synthesized for detecting hydrazine by using natural cinnamaldehyde as starting material.This probe exhibited significantly enhanced fluorescence response towards hydrazine over various common metal ions,anions,and amine compounds.The detection limit of probe FHT for hydrazine was as low as 0.14μmol·L^(-1),significantly lower than that of the threshold value of 0.312μmoi·L^(-1),imposed by the Environmental Protection Agency.Moreover,the proposed probe was able to detect hydrazine within wide pH(5-10)and linear detection ranges(0-110μmol·L^(-1)).This probe was employed for determining trace hydrazine in different environmental water samples.The probe FHT-loaded filter paper strips werea able to conveniently detect hydrazine of low concentration through distinct naked-eye and fluorescent color changes.Importantly,the probe FHT with low cytotoxicitywas successfullyapplied to visualize hydrazine in living Hela cells and zebrafish.