An imine-based colorimetric chemodosimeter for the detection of hypochlorite (ClO ^-) in aqueous media: its application in test strips and real water samples

Abstract: A highly selective colorimetric chemodosimeter ASAD, (E)-2-((4-(diethylamino)-2-hydroxybenzylidene)amino)-5-methoxybenzenesulfonic acid, was readily synthesized and characterized. The probe ASAD could selectively recognize hypochlorite (ClO ^-) through an oxidative cleavage of C=N bond with a color change from yellow to colorless and detected it down to a low concentration of 0.95 μ M. Importantly, ASAD could be employed as a practical and efficient optical sensor for ClO ^- in test strips and water samples. Moreover, the detection process of ASAD to hypochlorite was demonstrated by UV-vis spectroscopy, NMR titration and theoretical calculations. Graphical abstract: A highly selective colorimetric chemodosimeter ASAD was developed to selectively recognize hypochlorite (ClO ^-) through an oxidative cleavage of C=N bond with color change from yellow to colorless and could detect it down to a low concentration of 0.95 μ M.