| Abstract: | As a result of the low water content and high fat matrices in nuts, it is very difficult to simultaneously determine multi‐pesticides in trace levels. Here, a sample pretreatment method was developed in which, microwave‐assisted solvent extraction was firstly used to extract pesticides, and then a two‐step cleanup method was conducted combining freeze‐out with dispersive solid‐phase extraction to remove the lipidic matrix. By this way, 106 pesticides were simultaneously determined in the complicated nut sample by using an ultra‐high pressure liquid chromatography coupled with a tandem mass spectrometer. Average recoveries were 75.3–119.3% with relative standard deviations < 14% at three concentration levels. The limits of detection and quantification were in the ranges of 0.3–3.0 and 1.0–10.0 μg/kg, respectively. Furthermore, the method was successfully applied to the determination of pesticides in 180 commercial nut samples. |
