Chloro-hydroxyl-merocyanine based turn-on fluorescent probes for the detection of hydrazine in water and living cells

Hydrazine (N2H4) is a very important chemical reagent which has been widely used in the fields of chemistry industry, aerospace, pesticide production and others. However, N2H4 is highly toxic and prone to induce a variety of diseases. Hence, we designed two fluorescent probes (CH–NO1, CH–NO2) based on chloro-hydroxyl-merocyanine (CHMC) with similar recognition groups. The two probes were synthesized by a simple reaction coupling between CHMC dye and two alkyl bromine compounds. Both probes showed specific off-on response to N2H4 in aqueous solution with nanomolar LOD (28 nM for CH–NO1 and 38 nM for CH–NO2), and without interference by a range of amino acids, anions and cations. Moreover, CH–NO1 can be used for both environmental and biological monitoring of N2H4. © 2022 Elsevier Ltd