An ethyl thioglycolate-based chemosensor: Spectrophotometric detection of Fe3+ and fluorometric detection of Hg2+ with high selectivity.

A novel symmetric bianthracene derivative (D2) containing one benzene ring and two ethyl thioglycolates connecting to the benzene ring on both sides of the bianthracene unit was designed and synthesized. D2 can detect Fe3+ and Hg2+ in acetonitrile/water (6:4, v/v) solution via different changes of absorbance and fluorescence in the pH range from 3 to 10. D2 exhibits high colorimetric sensitivity for Fe3+ with low detection limit (1.87 × 10-5 mol/L). The absorbance intensity of D2 in acetonitrile/water solution show a linear response to Fe3+ in the wide concentration range of 0 -1000 μM, which is beneficial for quantitative analysis. D2 also displays highly selective fluorescent sensing for Hg2+ with a low detection limit of 1.07 µM over other metal ions and can accurately detect the existence of Hg2+ in water samples.