Two Benzocoumarin-based hydrazine chemodosimeters and their application in monitoring trace levels of hydrazine in soil, water, and urine samples

Abstract

Hydrazine is used widely in various sectors. This intensified environmental degradation during storage, transit, and sewage disposal. Hydrazine, a category 2B toxin, can go into the body via the skin and nasal passages. It could permanently harm the body. Developing selective recognition mechanisms is critical. In this study, two reaction-based sensors, Coumarin- benzobromobutanoate (CnBr) and Coumarin-Chalcone (CnBC) were developed for the selective detection of N2H4. When exposed to N2H4, CnBr and CnBC in H2O/DMSO (1:1) both produced green fluorescence with highest emission at 528 nm and 532 nm, respectively. The absence of a buffer would greatly simplify and facilitate real-time sample sensing. The addition-cyclisation-elimination cascade reaction supports the sensing mechanism for both CnBr and CnBC, as confirmed by 1H NMR and ESI-MS data. Other ions, amines, and amino acids didn't affect the probes’ hydrazine detection. CnBr and CnBC detects N2H4 at 1.05 µM and 1.01 µM respectively. The probe's practical application was demonstrated by its capacity to sense hydrazine in different soil samples, real water, and urine samples.