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Submitted to: Book Chapter
Publication Type: Book / Chapter Publication Acceptance Date: 6/5/2004 Publication Date: 1/1/2005 Citation: Lehotay, S.J. 2005 QUICK, EASY, CHEAP, EFFECTIVE, RUGGED AND SAFE (QUECHERS) APPROACH FOR DETERMINING PESTICIDE RESIDUES. METHODS IN BIOTECHNOLOGY. PESTICIDE PROTOCOLS. (19):239-261. Interpretive Summary: Technical Abstract: This chapter describes a simple, fast, and inexpensive method for the determination of pesticides in foods and potentially other matrices. The method, known as the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for pesticide residues involves the extraction of the sample with acetonitrile (MeCN) containing 1% acetic acid (HAc) and simultaneous liquid-liquid partitioning formed by adding anhydrous magnesium sulfate (MgSO4) plus sodium acetate (NaAc) followed by a simple cleanup step known as dispersive solid-phase extraction (SPE). The QuEChERS method is carried out by shaking a Teflon centrifuge tube which contains 1 mL of 1% HAc in MeCN plus 0.4 g anh. MgSO4 and 0.1 g anh. NaAc per g sample. The tube is then centrifuged, and a portion of the extract is transferred to a tube containing 50 mg primary secondary amine (PSA) sorbent plus 150 mg anh. MgSO4 per mL extract (the dispersive-SPE cleanup step). Then, the extract is centrifuged and transferred to autosampler vials for concurrent analysis by gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS-MS). Different options in the protocol are possible depending on alternate analytical instrumentation available, desired limit of quantitation (LOQ), scope of targeted pesticides, and matrixes tested. |
