Design of a dual sensing highly selective cyanide chemodosimeter based on pyridinium ring chemistry

[eng] A new chemodosimeter, Quino-P, recognizes the strongly nucleophilic cyanide by dual colorimetric and fluorescence 'off-on' signalling responses. Noteworthily, several other anions, even in significantly higher concentrations, induce no detectable photophysical perturbations. The chemodosimeter mechanism involves formation of a C4 cyano adduct, which exhibits an uncommon phenomenon of enhanced internal charge transfer interaction