Chromo-fluorogenic detection of cyanide ion with a cyanine probe

Abstract

Due to the extreme toxicity of cyanide in biological systems and its widespread presence in the environment, great efforts have been focused on developing sensitive and selective methods for cyanide detection. In this regard, a sulfo-cyanine dye 1 was evaluated as a colorimetric and fluorimetric probe for various anions. Chemosensing studies revealed that this compound exhib-ited remarkable selectivity and sensitivity for CN− in acetonitrile solution, with a marked colour change from cyan to colourless and the fluorescence emission was switched off. The detection lim-it was estimated to be as low as 0.45 μM, and the binding mode was studied using NMR techniques.