A water-soluble and reversible fluorescent probe for Al 3+ and F − in living cells

Based on fluorescein, a novel water-soluble and reversible fluorescent probe (Flu-Py) was designed and synthesized for the sequentially “ON–OFF–ON” fluorescent detection of Al3+ and F− in concentration range of 0–10 μmol L−1 and 0–30 μmol L−1, respectively, with high sensitivity and excellent selectivity. The detection limits for Al3+ and F− were 0.092 μmol L−1 and 0.112 μmol L−1, respectively. The binding mode and sensing mechanism of Flu-Py with Al3+ was verified by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculation. The “ON-OFF–ON” fluorescent property of Flu-Py upon the addition of Al3+ and F− was utilized for the imaging of living cells.