title: Determination of diflubenzuron and chlorbenzuron in fruits by combining acetonitrile-based extraction with dispersive liquid-liquid microextraction followed by high-performance liquid chromatography.
abstract: In this study, a simple and low-organic-solvent-consuming method combining an acetonitrile-partitioning extraction procedure followed by "quick, easy, cheap, effective, rugged and safe" cleanup with ionic-liquid-based dispersive liquid-liquid microextraction and high-performance liquid chromatography with diode array detection was developed for the determination of diflubenzuron and chlorbenzuron in grapes and pears. Ionic-liquid-based dispersive liquid-liquid microextraction was performed using the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate as the extractive solvent and acetonitrile extract as the dispersive solvent. The main factors influencing the efficiency of the dispersive liquid-liquid microextraction were evaluated, including the extractive solvent type and volume and the dispersive solvent volume. The validation parameters indicated the suitability of the method for routine analyses of benzoylurea insecticides in a large number of samples. The relative recoveries at three spiked levels ranged between 98.6 and 109.3% with relative standard deviations of less than 5.2%. The limit of detection was 0.005 mg/kg for the two insecticides. The proposed method was successfully used for the rapid determination of diflubenzuron and chlorbenzuron residues in real fruit samples.
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, P. R. China.
authors.forename: Chunqiang
authors.initials: C
authors.lastname: Ruan
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, P. R. China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Natural Pesticide and Chemical Biology, Ministry of Education, South China Agricultural University, Guangzhou, P. R. China.
authors.forename: Chenglan
authors.initials: C
authors.lastname: Liu
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D001555:Benzene Derivatives / Q000032:analysis*; D002623:Chemistry Techniques, Analytical; D002681:China; D002713:Chlorine / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D004132:Diflubenzuron / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D005638:Fruit / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry; D007094:Imides / Q000032:analysis*; D057230:Limit of Detection; D059627:Liquid Phase Microextraction; D010671:Phenylurea Compounds / Q000032:analysis*; D031989:Pyrus; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry; D027843:Vitis
chemical_list: C587464:3-methylimidazolium hexafluorophosphate; D000097:Acetonitriles; D001555:Benzene Derivatives; D007093:Imidazoles; D007094:Imides; D010671:Phenylurea Compounds; D012997:Solvents; C000608332:chlorbenzuron; D002713:Chlorine; D004132:Diflubenzuron; C032159:acetonitrile
keywords: Benzoylurea insecticides; Dispersive liquid-liquid microextraction; Fruits; High-performance liquid chromatography; Ionic liquids