Unusual Fluorescence Quenching-Based Al Sensing by an Imidazolylpiperazine Derivative. β-Cyclodextrin Encapsulation-Assisted Augmented Sensing.

We report in this paper an unusual β-cyclodextrin mediated-aluminum (III) ion sensing based on augmented quenching of fluorescence. The fluorescent sensing of metal ions by a new ligand prepared (L = 4-[{4-(1H-imidazol-1-yl)phenyl]imino}methyl]piperazine-1-carboxaldehyde) has been investigated as well as the effect of the supramolecular complex formation with β-CD. In aqueous solution, L shows an increase of fluorescence due to the interaction with β-cyclodextrin with a formation constant of 77 (± 12) M.