A quinoline-based Schiff base for significant fluorescent “turn-on” and absorbance-ratiometric detection of Al 3+

A novel quinoline-based Schiff base fluorescent sensor BQPA had been synthesized and characterized by common spectroscopic methods. It showed highly sensitive fluorescent enhancement (300-fold) and ratiometric absorbance for the determination of Al3+ with low detection limits of 31 nM in CH3CH2OH/H2O (1: 9, v/v) solution. The stoichiometry of the BQPA–Al3+ complex was 1:1, determined by Job plots curve and further confirmed by HRMS, 1H NMR titration and FT-IR spectrum. Moreover, the potential application of BQPA in the detection of Al3+ was estimated in real water samples.