A novel fluorescent probe based on the flexible dipicolylamine: Recognizing zinc(II) in aqueous solution and imaging in living cell

Abstract A novel fluorescent probe for Zn 2+ has been designed and synthesized based on a dipicolylamine group connected by a benzimidazole amide backbone. A comprehensive analysis of the recognition ability of the probe towards metal ions was conducted by ultraviolet absorption and fluorescence emission spectroscopy. Results demonstrated that the probe showed selective and sensitive fluorescence turn-on signaling behavior toward Zn 2+ in HEPES buffered (pH = 7.4) aqueous solution. The detection limit of this probe was calculated to be 5.10 × 10 −8  M for Zn 2+ . Fluorescent imaging inside HepG2 cells indicated potential application of the probe for detecting Zn 2+ ions in living cell imaging.