A highly selective fluorescence turn-on and reversible sensor for Al 3 + ion

A simple Schiff-base receptor 1 was prepared. It exhibits an "off-on-type" mode with high sensitivity in the presence of Al 3 + and shows a high association constant (5.89 × 10 6 M- 2) toward Al3 + in DMSO-H2O (4:6 v/v) solution. The addition of EDTA to receptor 1·Al3 + complex quenches the fluorescent intensity, indicating that receptor 1 serves as a reversible chemosensor. Crown