Anthracene- and pyrene-bearing imidazoles as turn-on fluorescent chemosensor for aluminum ion in living cells.

Abstract A newly designed 2-(2-Aminophenyl)-1 H -benzimidazole integrated anthracene/pyrene derivatives as efficient chemosensors were synthesized. The probes N-(anthracen-9-ylmethylene)-2-(1 H -benzo[d]imidazol-2-yl)aniline (ANP) and N-(pyren-1-ylmethylene)-2-(1 H -benzo[d]imidazol-2-yl)-aniline (PYP) exhibited high selectivity and sensitivity towards Al3+ ion over other interfering and competing cations in aqueous solution. Job's plot analysis reveals that the interaction of ANP/PYP with Al3+ was 1:1 binding stoichiometry. The detection limit of probes ANP and PYP for Al3+ ions were found to be 1.85 × 10−7 M and 1.08 × 10−7 M, respectively. The DFT/TD-DFT calculations have also been revealed that the ICT mechanism is responsible for the observed photophysical changes. Moreover, the probes ANP and PYP were applicable to image intracellular Al3+ ions in living cells via confocal fluorescence microscopy technique. Graphical abstract Image 1 Highlights • New anthracene and pyrene bearing Schiff base derivatives (ANP and PYP) were designed and synthesized. • The probes ANP and PYP served as an efficient fluorescent chemosensor towards Al3+ with high selectivity. • The 1:1 binding stoichiometry of the sensor ANP/PYP with Al3+ was established. • Reversibility of the chemosensor ANP/PYP was proved by experiments with EDTA. • ANP/PYP was successfully applied to fluorescence imaging of Al3+ in living cells. [ABSTRACT FROM AUTHOR]