title: Preparation of 4,4'-bis-(carboxyl phenylazo)-dibenzo-18-crown-6 dye and its application on ratiometric colorimetric recognition to Hg2+.
abstract: 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 Hg(2+)-selective ratiometric colorimetric behavior, with the maximum absorbance peak changing from 354 nm to 408 nm exclusively. Under the optimum conditions, the recognition to Hg(2+) 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.
authors.affiliation: Department of Material and Chemical Industry, West Anhui University, Lu'an 237012, China. yzhq2008@yahoo.com.cn
authors.forename: Zhengquan
authors.initials: Z
authors.lastname: Yan
authors.forename: Hu
authors.initials: H
authors.lastname: Lei
authors.forename: Nie
authors.initials: N
authors.lastname: Li
authors.forename: Lv
authors.initials: L
authors.lastname: Hong
mesh_terms: D003124:Colorimetry / Q000379:methods; D004396:Coloring Agents / Q000737:chemistry*; D043844:Crown Ethers / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008628:Mercury / Q000032:analysis*; D008958:Models, Molecular; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D004396:Coloring Agents; D043844:Crown Ethers; D014874:Water Pollutants, Chemical; D014867:Water; C002564:dibenzo-18-crown-6; D008628:Mercury