| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1235500 | Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy | 2011 | 5 Pages |
A multifunctional dye, 4,4′-bis-(carboxyl phenylazo)-dibenzo-18-crown-6 dye (BCADC) was designed and prepared via diazotization and coupling reaction of dibenzo-18-crown-6 with p-amino benzoic acid. The dye, combining crown ether ring, azo and carboxyl group, exhibits well-defined Hg2+-selective ratiometric colorimetric behavior, with the maximum absorbance peak changing from 354 nm to 408 nm exclusively. Under the optimum conditions, the recognition to Hg2+ has a linear range of 2.5–58 × 10−7 mol L−1 with a 0.9978 correlation coefficient. The method was applied to analyse 3 environmental water samples with a detection limit of 2.9 × 10−8 mol L−1 and a relative standard deviation (R.S.D.) lower than 3.7% (n = 5). The action mechanism between BCADC and metal ions was discussed by means of Job's plots and theoretical calculations.
Graphical abstract. In this contribution, a multifunctional dye, 4,4′-bis-(carboxyl azobenzene)-dibenzo-18-crown-6 dye (BCADC) was designed and prepared via diazotization and coupling reaction of dibenzo-18-crown-6 with p-amino benzoic acid. The dye, combining crown ether ring, azo and carboxyl group, exhibits well-defined Hg2+-selective ratiometric colorimetric behavior, with the maximum absorbance peak changing from 354 nm to 408 nm exclusively. Under the optimum conditions, the recognition to Hg2+ has a linear range of 2.5–58 × 10−7 mol L−1 with a 0.9978 correlation coefficient. The method was applied to analyse 3 environmental water samples with a detection limit of 2.9 × 10−8 mol L−1 and a relative standard deviation (R.S.D.) lower than 3.7% (n = 5). The action mechanism between BCADC and metal ions was discussed by means of Job's plots and theoretical calculations.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A multifunctional colorimetric sensor with crown ether ring, azo and carboxyl group. ► Different metal ions act with the functional groups with different action mechanisms. ► The interaction between Hg2+ and BCADC is exclusive. ► The reaction mechanism is confirmed by means of experimental and theoretical proofs. ► An effective ratiometric colorimetric recognition to Hg2+ is developed.
