title: New method based on combining ultrasonic assisted miniaturized matrix solid-phase dispersion and homogeneous liquid-liquid extraction for the determination of some organochlorinated pesticides in fish.
abstract: In this study, ultrasonic assisted miniaturized matrix solid-phase dispersion (US-MMSPD) combined with homogeneous liquid-liquid extraction (HLLE) has been developed as a new method for the extraction of organochlorinated pesticides (OCPs) in fish prior to gas chromatography with electron capture detector (GC-ECD). In the proposed method, OCPs (heptachlor, aldrin, DDE, DDD, lindane and endrin) were first extracted from fish sample into acetonitrile by US-MMSPD procedure, and the extract was then used as consolute solvent in HLLE process. Optimal condition for US-MMSPD step was as follows: volume of acetonitrile, 1.5 mL; temperature of ultrasound, 40°C; time of ultrasound, 10 min. For HLLE step, optimal results were obtained at the following conditions: volume of chloroform, 35 μL; volume of aqueous phase, 1.5 mL; volume of double distilled water, 0.5 mL; time of centrifuge, 10 min. Under the optimum conditions, the enrichment factors for the studied compounds were obtained in the range of 185-240, and the overall recoveries were ranged from 39.1% to 81.5%. The limits of detection were 0.4-1.2 ng g(-1) and the relative standard deviations for 20 ng g(-1) of the OCPs, varied from 3.2% to 8% (n=4). Finally, the proposed method has been successfully applied to the analysis of the OCPs in real fish sample, and satisfactory results were obtained.
authors.affiliation: Department of Analytical Chemistry, Faculty of Chemistry, Iran University of Science and Technology, Narmak, Tehran 16846, Iran.
authors.forename: Farahnaz
authors.initials: F
authors.lastname: Rezaei
authors.forename: Mohammad-Reza Milani
authors.initials: MR
authors.lastname: Hosseini
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000818:Animals; D002725:Chloroform / Q000737:chemistry; D002849:Chromatography, Gas / Q000379:methods*; D005399:Fishes / Q000378:metabolism*; D006843:Hydrocarbons, Chlorinated / Q000032:analysis* / Q000737:chemistry; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction / Q000379:methods*; D008832:Microchemistry / Q000379:methods; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013696:Temperature; D013997:Time Factors; D014465:Ultrasonics / Q000379:methods*; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D012997:Solvents; D014867:Water; D002725:Chloroform; C032159:acetonitrile