Effect of background derivatization on the signal enhancement of pesticide residues extracted from edible oils

• Published in: Journal of separation science Vol. 36; no. 24; pp. 3926 - 3933
• Main Authors: Deme, Pragney, Azmeera, Tirupathi, Bethala, Prabhavathi Devi L.A., Jonnalagadda, Padmaja R., Rachapudi, Prasad B.N., Upadhyayula, Vijaya Sarathi V.R.
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.12.2013; Wiley; Wiley Subscription Services, Inc
• Subjects: Biological and medical sciences; Derivatization; Edible; Edible oils; Fat industries; Food industries; Fundamental and applied biological sciences. Psychology; Gas chromatography; Gas Chromatography-Mass Spectrometry; Mass spectrometry; Negative chemical ionization; Pesticide residues; Pesticide Residues - analysis; Pesticide Residues - chemistry; Pesticide Residues - isolation & purification; Pesticides; Plant Oils - chemistry; Plants, Edible - chemistry; Validation; Negative chemical ionization; Chemical analysis; Coupled method; Silylation; Pesticides; Derivatization; Edible oil; Contamination; Chemical ionization; Gas chromatography; Pesticide residues; Residue; Negative ion; Edible oils; Mass spectrometry; Quantitative analysis
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.201300454

The effect of background derivatization on the signal enhancement of pesticide residues extracted from edible oil samples was studied by GC with negative chemical ionization MS. The analytes were extracted by a solvent extraction process, and the extract was subjected to rapid low‐temperature fat precipitation. The residual fatty acids were silylated by derivatization with N,O‐bis(trimethylsilyl)trifluoroacetamide. The chromatograms obtained from the derivatized samples showed higher signal intensity and lower detection levels when compared to the direct analysis without derivatization. The sensitivity levels of the method are either better or comparable to that of previously reported methodologies. The LODs of the analyzed organochlorine, organophosphorus, and synthetic pyrethroid residues in sunflower, rice bran, and ground oil samples were in the range of 0.02–0.5 ng/g, and the LOQs were in the range of 0.1–2 ng/g. The intraday and interday accuracies were in the range of 81–116% with RSDs less than 14%. The recoveries obtained were in the range of 53–89% with the RSD values less than 13% for all the studied pesticide residues.