title: A simple and efficient multi-residue method based on QuEChERS for pesticides determination in palm oil by liquid chromatography time-of-flight mass spectrometry.
abstract: In this study, a rapid, specific and sensitive multi-residue method based on acetonitrile extraction followed by dispersive solid-phase extraction (d-SPE) clean-up was implemented and validated for multi-class pesticide residues determination in palm oil for the first time. Liquid-liquid extraction followed by low-temperature precipitation procedure was evaluated in order to study the freezing-out clean-up efficiency to obtain high recovery yield and low co-extract fat residue in the final extract. For clean-up step, d-SPE was carried out using a combination of anhydrous magnesium sulphate (MgSO(4)), primary secondary amine, octadecyl (C(18)) and graphitized carbon black. Recovery study was performed at two concentration levels (10 and 100 ng g(-1)), yielding recovery rates between 74.52% and 97.1% with relative standard deviation values below 10% (n = 6) except diuron. Detection and quantification limits were lower than 5 and 9 ng g(-1), respectively. In addition, soft matrix effects (≤±20%) were observed for most of the studied pesticides except malathion that indicated medium (20-50%) matrix effects. The proposed method was successfully applied to the analysis of suspected palm oil samples.
authors: Environmental Research Group, Department of Chemistry, University of Malaya, Kuala Lumpur 50603, Malaysia. elham.sobhanzadeh@yahoo.com
authors: Elham
authors: E
authors: Sobhanzadeh
authors: Nor Kartini
authors: NK
authors: Abu Bakar
authors: Mhd Radzi
authors: MR
authors: Bin Abas
authors: Keivan
authors: K
authors: Nemati
mesh_terms: D002853:Chromatography, Liquid; D004785:Environmental Pollutants / Q000032:analysis* / Q000737:chemistry; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D013058:Mass Spectrometry; D000073878:Palm Oil; D010573:Pesticide Residues / Q000032:analysis* / Q000737:chemistry; D010938:Plant Oils / Q000737:chemistry*
chemical_list: D004785:Environmental Pollutants; D010573:Pesticide Residues; D010938:Plant Oils; D000073878:Palm Oil