An Acid-triggered Reactive and Enhanced Fluorescent Probe for Selective Detection of Al3+/H+ and its Application in Real Water Samples and Living Cells

A reactive fluorescent “turn-on” probe ( di-PIP ) with imine-linked dual phenanthro[9,10- d ]imidazole luminophore have been conveniently prepared as an Al 3+ and H + dual functional receptor. di-PIP displayed high selectivity and sensitivity towards Al 3+ ion in DMF/HEPES accompanied by fluorescence blue-shift and a good linear relationship as well as a low detection limit of 30.5 nmol·L –1 , which can root from the synergetic functions of the decomposition reaction of di-PIP promoted by acidic Al 3+ and the coordination effect between decomposition product and Al 3+ . Intriguingly, it was found that hydrogen ion H + can be sufficient for simulating the fluorescence enhancing of di-PIP . 1 H NMR titration and MS analyses for elucidation of the intermediate structure further revealed that the acid-triggered decomposition reaction resulted in the rapid, and sensitive sensing to Al 3+ and H + . In addition, the probe di-PIP could be successfully applied to the detection of Al 3+ in real water samples, and also utilized to visualize Al 3+ and H + in the living cells.