|HAN, LIJUN - China Agricultural University|
|MATARRITA-RODRIGUEZ, JESSIE - Universidad De Costa Rica|
Submitted to: Journal of Chromatography A
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/18/2016
Publication Date: 4/22/2016
Citation: Han, L., Matarrita-Rodriguez, J.A., Sapozhnikova, Y.V., Lehotay, S.J. 2016. Evaluation of a recent product to remove lipids and other matrix co-extractives in the analysis of pesticide residues and environmental contaminants in foods. Journal of Chromatography A. 1449:17-29. doi: 10.1016/j.chroma.2016.04.052.
Interpretive Summary: Analysis of pesticide residues and environmental contaminants in diverse food types is an important application for improved food safety and environmental health, and monitoring is routinely conducted in countless laboratories worldwide for many purposes. One of the main challenges in detecting, identifying, and quantifying ultratrace amounts of contaminants in complex foods is sample cleanup, which involves the isolation of the residues of concern from the myriad of food matrix components. In this study, a new commercial product was evaluated for sample cleanup, and results showed it to be more effective than other common cleanup techniques currently available. This is the first independent scientific report about the novel product, and the advantages and disadvantages are presented. The new cleanup technique is expected to be widely used in the future to ease the analysis of chemical residues in food, and ultimately improve monitoring results.
Technical Abstract: This study demonstrates the application of a novel lipid removal product to the residue analysis of 65 pesticides and 52 environmental contaminants in kale, pork, salmon, and avocado by fast, low pressure gas chromatography – tandem mass spectrometry (LPGC-MS/MS). Sample preparation involves QuEChERS extraction followed by use of EMR-Lipid (“enhanced matrix removal of lipids”) and an additional salting out step for cleanup. The optimal amount of EMR-Lipid was determined to be 500 mg for 2.5 mL extracts for most of the analytes. The co-extractive removal efficiency by the EMR-Lipid cleanup step was 83-98% for fatty samples and 79% for kale, including 76% removal of chlorophyll. Matrix effects were typically less than +\- 20%, in part because analyte protectants were used in the LPGC-MS/MS analysis. The recoveries of polycyclic aromatic hydrocarbons and diverse pesticides were mostly 70-120%, whereas recoveries of nonpolar polybrominated diphenyl ethers and polychlorinated biphenyls were mostly lower than 70% through the cleanup procedure. With the use of internal standards, method validation results showed that 76-85 of the 117 analytes achieved satisfactory results (recoveries of 70-120% and RSD = 20%) in pork, avocado, and kale, while 53 analytes had satisfactory results in salmon. Detection limits were 5-10 ng/g for all but a few analytes. EMR-Lipid is a new sample preparation tool that serves as another useful option for cleanup in multiresidue analysis, particularly of fatty foods.