A fluorescent and colorimetric chemosensor for selective detection of aluminum in aqueous solution

We have synthesized a new Schiff base 1, which detects Al3+ through fluorescence and naked eye in aqueous solution. The sensor 1 exhibited selective and sensitive recognition toward Al3+ via significant fluorescence enhancement (31-fold). Moreover, it showed a significant color change from colorless to yellow. The complex formation was proposed to be 1:1 ratio, based on the Job plot, ESI-mass spectrometry analysis, 1H NMR titration, and IR analysis. The detection limit was 1.00 μM, which is below the WHO acceptable limit (1.85 μM) in drinking water. In addition, the sensor 1 could be recyclable simply through treatment with a proper reagent such as EDTA.