Highly selective fluorescence turn-on sensor for Cu2+ ions and its application in confocal imaging of living cells.

A novel ethylenediamine (EDA) based chemosensor 5 [dimethyl 2,2′-((3-oxocyclohex-1-ene-1,2-diyl)bis(azanediyl))dibenzoate] has been designed and synthesized for the turn on fluorescence sensing of Cu 2+ ions. The molecular geometry configuration of 5 is identified by X-ray diffraction and its corresponding orbital electron distributions are predicted by density functional theory (DFT). The probe 5 exhibits strong and selective complexing ability towards Cu 2+ over the other metal ions tested in both acetonitrile and aqueous solvent systems. MeCN-HEPES buffer system is more suitable for the selective fluorescence sensing of Cu 2+ ions. In addition, the lowest detection limit is 0.30 μM for Cu 2+ ions. This probe has also been applied successfully for the confocal fluorescence imaging of MDCK cells. Therefore, this probe can be used in both the environmental and biological systems for the detection of Cu 2+ . [ABSTRACT FROM AUTHOR]