title: Combination of ultrasound-assisted ionic liquid dispersive liquid-phase microextraction and high performance liquid chromatography for the sensitive determination of benzoylureas pesticides in environmental water samples.
abstract: This paper describes a new method for rapid and sensitive determination of diflubenzuron, flufenoxuron, triflumuron and chlorfluazuron in water samples by ultrasound-assisted ionic liquid dispersive liquid-phase microextraction in combination with HPLC. Ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([C(6)MIM][PF(6)]) was used as the extraction solvent for the enrichment of four benzoylurea (BU) pesticides. Factors such as volume of [C(6)MIM][PF(6)], sonication time, sample pH, extraction time, centrifuging time and salting-out effect were systematically investigated. Under the optimum conditions, an excellent linear relationship was achieved in the range of 1.0-100 μg/L. The detection limits varied from 0.21 to 0.45 μg/L and the precision of the method was below 6.9% (RSD, n=6). The proposed method was successfully applied for the determination of these BU pesticides in water samples and excellent spiked recoveries were achieved. All these results demonstrated that this procedure provided a new simple, rapid, easy to operate, efficient and sensitive method for the analysis of BU pesticides in aqueous samples.
authors.affiliation: State Laboratory of Petroleum Resource and Prospecting, Key Laboratory of Earth Prospecting and Information Technology, College of Geosciences, China University of Petroleum, Beijing Campus (CUP), Beijing, PR China. zhouqx@cup.edu.cn
authors.forename: Qingxiang
authors.initials: Q
authors.lastname: Zhou
authors.forename: Xiaoguo
authors.initials: X
authors.lastname: Zhang
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D007477:Ions; D057230:Limit of Detection; D010575:Pesticides / Q000032:analysis*; D015203:Reproducibility of Results; D014465:Ultrasonics; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D007477:Ions; D010575:Pesticides; D014874:Water Pollutants, Chemical