A new fluorescent turn-on chemodosimeter for mercury(II) based on dithioacetal-substituted triphenylimidazole

In this paper, we demonstrate a new fluorescent turn-on chemodosimeter for Hg2+ determination. The chemodosimeter contains a triphenylimidazole fluorophore and an Hg2+-responsive dithioacetal moiety. In the presence of Hg2+, the probe displays a characteristic turn-on mode at 527 nm in its emission spectrum due to the irreversible Hg2+-promoted deprotection of the dithioacetal group. With the aid of the fluorescence spectrometer, the chemodosimeter in the dimethylformamide/H2O (7/3, v/v) mixed solvent (2.0 μM) exhibits a detection limit of 4.3 nM (S/N=3). Interferences from other common cations associated with Hg2+ analysis are effectively inhibited.