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BACKGROUND: A method has been developed based on a three–phase system, followed by dispersive liquid–liquid microextraction for the extraction of seven pesticides from soya milk prior to analysis by gas chromatography‐flame ionization detection. The base of this method is the different extraction capability of the components of soya milk according to each of the phases involved. In this procedure, a homogeneous solution consisting of soya milk and a water–miscible solvent (acetonitrile) is separated into two phases in the presence of Na2SO4 and the analytes are extracted into the produced acetonitrile droplets. The acetonitrile phase is mixed with a pre‐concentration solvent to perform the next microextraction procedure for further enrichment of the analytes. RESULTS: Limits of detection and quantification were reached in the ranges of 0.11–0.35 and 0.35–1.20 µg L−1, respectively. Enrichment factors and extraction recoveries were in the ranges of 562–933 and 56–93%, respectively. Relative standard deviations were ≤7% for intra– (n = 6) and inter–day (n = 5) precisions at two concentrations of 10 and 50 µg L−1 of each analyte. CONCLUSION: The proposed method was applied to the analysis of pesticides in soya milk samples at µg L−1 concentrations. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

BACKGROUND A combination of magnetic solid‐phase extraction using an efficient and cheap magnetic sorbent obtained from sand and dispersive liquid–liquid microextraction has been developed for the extraction of nine multiclass pesticides (clodinafop‐propargyl, haloxyfop‐R‐methyl, fenoxaprop‐P‐ethyl, oxadiazon, penconazole, diniconazole, chlorpyrifos, fenazaquin, and fenpropathrin) from commercial fruit juices (sour cherry, pomegranate, grape, watermelon, orange, apricot, and peach juices). The enriched pesticides were determined by gas chromatography–flame ionization detector and gas chromatography–mass spectrometry. The sorbent was natural iron oxide entrapped in silica along with some impurities. In this method, to extract the analytes from the samples, an appropriate amount of the magnetic sorbent (at mg level) is added. Then the sorbent particles are isolated from the solution using an external magnetic field and the adsorbed analytes are desorbed from the sorbent by acetone. In the following, a dispersive liquid–liquid microextraction procedure is carried out to concentrate the analytes more and to reach low limits of detection. RESULTS: Under optimized extraction conditions, the method revealed satisfactory repeatability (relative standard deviation ≤8% for intra‐day and inter‐day precision), reasonable extraction recovery (43.3–55.9%), high enrichment factors (433–559), and low limits of detection (0.45–0.89 μg L−1). CONCLUSION: The method was applied in the analysis of pesticides in various fruit juices. Chlorpyrifos was found in peach juice at a concentration of 27 ± 2 μg L−1 (n = 3) using a gas chromatography–flame ionization detector. To verify the results, the peach juice was also injected into gas chromatography–mass spectrometry after applying the proposed extraction method. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]