A phenothiazine-based “turn-on” fluorescent probe for the detection of hydrazine in water, soil, plant and food samples†

Abstract

As a common chemical raw material, even a small amount of hydrazine (N₂H₄) residue can cause irreversible damage to the environment. Therefore, the exploration and development of an effective method for N₂H₄ detection is undoubtedly of far-reaching research value. This work presents the design and synthesis of three new fluorescent probes, ZWQ-1, ZWQ-2 and ZWQ-3, for the specific detection of N₂H₄. These three probes ZWQ-1, ZWQ-2 and ZWQ-3 had high selectivity, photostability and large Stokes shifts (170 nm). The calculated detection limits for N₂H₄ were as low as 7.27 μM, 1.05 nM and 26.65 nM for ZWQ-1, ZWQ-2 and ZWQ-3, respectively. It is noteworthy that ZWQ-2 exhibits a significant fluorescence enhancement response up to 550-times for N₂H₄, whereas ZWQ-1 shows a stable response to N₂H₄ detection in a very short period of time (about 1 minute). These probes have been demonstrated in practice for the effective detection of N₂H₄ in water, soil and food samples, providing a good tool for detecting N₂H₄ in the fields of environmental protection and food safety.