Discriminating detection between F^- and CN^- by naked eye from Schiff base sensor

A simple colorimetric and turn-on fluorescence receptor 1 was prepared and its cations and anions sensing properties were investigated in CH₃CN solution. Receptor 1 can selectively sense F^- and CN^- based on distinct color changes among a series of ions. Receptor 1 displayed a highly selective colorimetric response to fluoride anions based on a hydrogen bonding interaction process and fluorescent with colorimetric response to cyanide anions based on a generation of a cyanide adduct. The detection limit of receptor 1 toward F^- and CN^- ion was determined to be 0.28 ppm and 0.41 ppm, respectively. The two detection limit values were sufficiently low to detect submicromolar concentration of the F^- and CN^-.