A highly selective colorimetric and fluorescent chemosensor for Al(III) based-on simple naphthol in aqueous solution.

A colorimetric and fluorescent chemosensor (L) for Al(III) was synthesized and fully characterized. L could be both used as a colorimetric and fluorescent chemosensor for the detection of Al(3+) ions with low detection limit (8.87×10(-7) M) in CH3CN-H2O (1:1, v/v) solution. The binding ratio of L-Al(3+) was determined from the Job plot (absorption and fluorescence spectra) and MALDI-TOF MS data to be 1:1. The binding constant (Ka) of Al(3+) binding to L was calculated to be 4.8×10(5) M(-1) from a Benesi-Hildebrand plot. Moreover, the binding site of L with Al(3+) was determined by (1)H NMR titration experiment.