摘要

A new benzimidazole base turn-on fluorescent and ratiometric absorption chemosensor (L) bearing bidentate ligand for detection of Cu2+ was designed and synthesized. Fluorescence and UV-vis spectra studies demonstrated that L can detect Cu2+ ions in aqueous solution using fluorescence enhancement and ratiometric absorption sensing over a wide pH range. Both fluorescent and ratiometric absorption sensing of L for Cu2+ possessed high selectivity and sensitivity over other competitive metal ions and had low detection limit. Job's plot, mass spectra and DFT calculation indicated the sensing mechanism is the complex formation between L and Cu2+ with 1:2 stoichiometry. Fluorescence images of HepG2 in the absence and presence of Cu2+ displayed L had cell permeability and detection ability for Cu2+ in live cells.