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Evaluation of the QuEChERS sample preparation approach for the analysis of pesticide residues in olives
Author(s) -
Cunha Sara C.,
Lehotay Steven J.,
Mastovska Katerina,
Fernandes José O.,
Beatriz Maria,
Oliveira P. P.
Publication year - 2007
Publication title -
journal of separation science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.72
H-Index - 102
eISSN - 1615-9314
pISSN - 1615-9306
DOI - 10.1002/jssc.200600410
Subject(s) - quechers , pesticide residue , chromatography , pesticide , chemistry , sample preparation , extraction (chemistry) , residue (chemistry) , clean up , biochemistry , agronomy , biology
This paper describes the use of a quick, easy, cheap, effective, rugged, and safe (QuEChERS) method for extraction and cleanup of 16 pesticide residues of interest in olives and olive oil. These products contain a high lipid content, which can adversely affect pesticide recoveries and harm traditional chromatographic systems. For extraction, the main factors (oil and water content) were studied and optimized in experiments to maximize pesticide recoveries. Dispersive SPE with different sorbents was also investigated to minimize matrix coextractives and interferences. For analysis, a new automated DSI device was tested in GC‐MS to avoid nonvolatile coextractives from contaminating the instrument. LC‐MS/MS with positive ESI was used for those pesticides that were difficult to detect by GC‐MS. The final method was validated for olives in terms of recoveries, repeatabilities, and reproducibilities using both detection techniques. The results demonstrated that the method achieved acceptable quantitative recoveries of 70–109% with RSDs <20% for DSI‐GC‐MS and 88–130% with RSDs <10% for LC‐MS/MS, and LOQ at or below the regulatory maximum residue limits for the pesticides were achieved.