Phenoxazine-based fluorescence chemosensor for selective detection of cyanide

Purpose A highly selective cyanide phenoxazine-based fluorescence chemosensor POH was created to detect cyanide (CN) ions. Design/methodology/approach A malonitrile was added to a phenoxazine fluorophore to make this widely available chemosensor. By fluorescence spectroscopy, the sensor POH showed turn-off fluorescence emission for CN with 2:1 binding stoichiometry in CH3CN/H2O (90:10 v/v) medium. Findings The detection limits for CN were 9.8 × 10−9 M, which were much lower than WHO standards. NMR and FT-IR investigations backed up the suggested sensor POH mechanism. Originality/value The detection CN method should be applicable in a number of situations, where the CN anion for fresh water and drinking water has to be quickly and accurately analyzed. Graphical abstract