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Title: Technologies for the detection of chemical and biological contaminants in foods
Authors: Sapozhnikova T
Journal: LC GC N Am
Accepted date: 2014 Mar 18
Interpretive summary: In this study we compared efficiency of the three sorbents for d-SPE clean-up of fish extracts for the analysis of pesticides and environmental contaminants: C18+PSA, Z-Sep and Z-Sep Plus. C18+PSA removed the highest amounts of co-extractive materials by weight (80%), followed by Z-Sep (66%) and Z-Sep Plus (55%). In terms of recoveries of target analytes, Z-sep provided the highest recoveries for most of the contaminants, and Z-sep Plus showed greatest standard deviations, perhaps, caused by matrix interferences. Recoveries of analytes not normalized to ISTDs, were 2-3 times lower for all classes, except for pesticides, reflecting the loss of the corresponding ISTDs during the sample preparation. Two major co-extractive compounds identified in the extracts that contributed to MEs were oleic and octadecanoic acid, and d-SPE with Z-Sep removed these compounds most effectively. Peak shapes and widths were altered by co-eluting matrix interferences as we observed in the case of o,pí-DDE. Calculated MEs for TPP and o,pí-DDE based on peak areas were lowest for d-SPE with C18+PSA, followed by Z-Sep and Z-Sep Plus, however they were less than 3% for all the treatments when normalized to ISTDs, indicating the need of using ISTD for ME compensation. Finally, Pearson correlations were reported for compoundsí recoveries, tR and log Kow values.