A simple two-output near-infrared fluorescent probe for hydrazine detection in living cells and mice

Hydrazine is an important reactive base in chemistry, pharmacy and agriculture and an effective propellant in aeronautics and astronautics. However, tiny leakage might induce serious environmental contamination and fatal biological damage. Thus, how to rapidly detect hydrazine with high selectivity and sensitivity is of significance and challenge. In this report, we demonstrate a hydrazine-specific fluorescent probe on the modulation of intramolecular charge transfer process. This probe contains a 4-bromobutyl group as a recognition site for hydrazine anchored on the fluorescent dye. Leaving of 4-bromotutylate moiety leads to a marked NIR fluorescent emission at 715 nm induced by hydrazine. Additionally, presence of hydrazine leads to a color change from green to blue-purple and a ratiometric UV-vis absorption change with a clear isosbestic point at 635 nm. The good linear relationship between fluorescence intensity and concentration of hydrazine results in a low detection limit of 5.09 ppb. The color and fluorescence two-output signals are preferable for qualitative and quantitative detection of hydrazine with high sensitivity and specificity. More importantly, the probe is also successfully applied to visualize hydrazine in living both cells and mice.