title: Determination of three estrogens and bisphenol A by functional ionic liquid dispersive liquid-phase microextraction coupled with ultra-high performance liquid chromatography and ultraviolet detection.
abstract: A hydroxyl-functionalized ionic liquid, 1-hydroxyethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, was employed in an improved dispersive liquid-phase microextraction method coupled with ultra high performance liquid chromatography for the enrichment and determination of three estrogens and bisphenol A in environmental water samples. The introduced hydroxyl group acted as the H-bond acceptor that dispersed the ionic liquid effectively in the aqueous phase without dispersive solvent or external force. Fourier transform infrared spectroscopy indicated that the hydroxyl group of the cation of the ionic liquid enhanced the combination of extractant and analytes through the formation of hydrogen bonds. The improvement of the extraction efficiency compared with that with the use of alkyl ionic liquid was proved by a comparison study. The main parameters including volume of extractant, temperature, pH, and extraction time were investigated. The calibration curves were linear in the range of 5.0-1000 μg/L for estrone, estradiol, and bisphenol A, and 10.0-1000 μg/L for estriol. The detection limits were in the range of 1.7-3.4 μg/L. The extraction efficiency was evaluated by enrichment factor that were between 85 and 129. The proposed method was proved to be simple, low cost, and environmentally friendly for the determination of the four endocrine disruptors in environmental water samples.
authors: School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China.
authors: Yuehuang
authors: Y
authors: Jiang
authors: School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China.
authors: Tingting
authors: T
authors: Tang
authors: School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China.
authors: Zhen
authors: Z
authors: Cao
authors: Department of Chemistry, East China Normal University, Shanghai, P. R. China.
authors: Guoyue
authors: G
authors: Shi
authors: School of Ecological and Environmental Sciences, East China Normal University, Shanghai, P. R. China.
authors: Tianshu
authors: T
authors: Zhou
mesh_terms: D001559:Benzhydryl Compounds / Q000032:analysis*; D002138:Calibration; D002412:Cations; D002851:Chromatography, High Pressure Liquid; D052244:Endocrine Disruptors / Q000032:analysis*; D004964:Estriol / Q000737:chemistry; D004967:Estrogens / Q000032:analysis*; D004970:Estrone / Q000737:chemistry; D006860:Hydrogen Bonding; D006863:Hydrogen-Ion Concentration; D017665:Hydroxyl Radical; D052578:Ionic Liquids; D057230:Limit of Detection; D059627:Liquid Phase Microextraction; D010636:Phenols / Q000032:analysis*; D012997:Solvents / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013696:Temperature; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000032:analysis; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D002412:Cations; D052244:Endocrine Disruptors; D004964:Estriol; D004967:Estrogens; D004970:Estrone; D017665:Hydroxyl Radical; D052578:Ionic Liquids; D010636:Phenols; D012997:Solvents; D014874:Water Pollutants, Chemical; C006780:bisphenol A; D000098826:Bisphenol A Compounds
keywords: Dispersive liquid-phase microextraction; Endocrine disruptors; Ultra-high performance liquid chromatography; lonic liquids