A new salen-based chiral Schiff base, 6,6'-((1E,1'E)-((1R,2R)-cyclohexane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(2,4-dibromophenol) (H2L) has been designed and synthesized. The H2L is a fluorescent chemical sensor that can rapidly and precisely detect harmful heavy metal ions of Hg2+ and Pb2+ with well-separated excitation and emission wavelengths. Single-crystal X-ray diffraction analysis confirmed the structure of H2L. The binding of Hg2+/Pb2+ causes a change in the emission behavior of the H2L from weakly fluorescent to highly fluorescent through the CHEF effect and inhibits the PET process. The H2L exhibited immense selectivity and tremendous sensitivity, with LOD values of 8.29 nM and 7.65 nM for Hg2+ and Pb2+, respectively. The 1:1 binding mode of H2L.Hg2+ and H2L.Pb2+ is validated by Job's plot, 1H NMR titration, and ESI-MS investigations. In addition, H2L has been used to detect Hg2+/Pb2+ ions in real water samples, paper strips, and intracellularly in HeLa cells

You have access to this article

Please wait while we load your content... Something went wrong. Try again?