An alternative approach to develop a highly sensitive and selective chemosensor for the colorimetric sensing of cyanide in water

By utilizing a new indirect trick, an old and cheap compound, zincon (2-carboxy-2'-hydroxy-5'-sulfoformazylbenzene), was found to be a novel'' highly sensitive and selective chemosensor for cyanide in pure aqueous solutions, with a detection limit of 0.13 ppm and a color change that could be observed by the naked eye.