A dual functional turn-on non-toxic chemosensor for highly selective and sensitive visual detection of Mg and Zn: the solvent-controlled recognition effect and bio-imaging application.

A new dual functional turn-on chemosensor, 2,6-diformyl-4-methylphenol-di(isoquinolinyl-1-hydrazone) (HL), has been developed, which could highly selectively discriminate Mg and Zn in different solvent systems. The chemosensor HL exhibits rapid visual turn-on fluorescence enhancing recognition toward Mg/Zn, which is not interfered by other cations, especially for respective congeners Ca/Cd. The remarkable fluorescence enhancement (71-fold or 11-fold) was observed after adding Mg in acetonitrile or Zn in DMF-HO solvent systems. Additionally such a solvent medium-controlled platform could achieve the quantitative determination of Mg and Zn quantitation with low detection limits of 2.97 × 10 M and 3.07 × 10 M, respectively. Furthermore, the turn-on fluorescence sensing mechanism is also investigated by H NMR, FT-IR and ESI-MS spectroscopy. Density functional theory (DFT) calculations derive optimized geometries of HL and its complexes. Notably, non-toxic HL also can be successfully applied as a visual probe for the practical determination of Mg/Zn in MCF-7 cells, Zebrafish larvae, syrup and water samples, which might provide extensive application in biology and medicine fields.