Benzotiazole‐Based Colorimetric Chemosensor for the Effective Detection of Hazardous Cyanide Ions

Abstract

A new hydrazone based on 5-nitrofurfural and 2-hydrazinobenzothiazole (L) was introduced as a colorimetric chemosensor for rapid, selective, and sensitive detection of CN À ions in aqueous media. The chemosensor L was characterized using spectral methods such as FT-IR, 1 H, 13 C NMR, UV-Vis, and mass spectrometry. The interaction of L with the CN À ion provides a marked color change from yellow to blue-green or blue, depending on the concentration of cyanide ions. The change in colour as well as in absorption maxima make it possible to detect CN À ions with the naked eye. The detection limit of the chemosensor L is 0.26 μM, which is below the WHO limit for cyanide ions in drinking water. Other competing anions (