Two fluorescence turn-on Schiff׳s base chemosensors for Cu2+ ions

Abstract Two new salicylaldehyde Schiff base chemosensors have been synthesized. Their crystal structures, photophysical properties as well as recognition properties for Cu 2+ ions have also been examined. Their absorption peaks exhibit obvious blue shift upon the addition of Cu 2+ to a HEPES buffer–methanol (3:7, v/v) solution of the compounds. The compounds are found to be able to recognize Cu 2+ ions with fluorescence turn-on response in aqueous solution owing to the hydrolysis of the hydrazone bond in the Schiff׳s base compounds induced by Cu 2+ ions.