Simultaneous determination of seven pesticide residues in soil samples using ultrasound‐assisted dispersive solid‐phase extraction combined with UHPLC–MS/MS

Abstract

AbstractA novel and reliable method for the determination of seven pesticide residues (hexaconazole, flutriafol, triadimenol, tebuconazole, diniconazole, fipronil and picoxystrobin) in soil samples was developed by using ultrasound‐assisted dispersive solid‐phase extraction combined with ultra high performance liquid chromatography and tandem mass spectrometry. In this approach, the target analytes were first extracted from the soil samples into acetonitrile, and the ultrasound technique was applied to increase the extraction efficiency. Next, a dispersive solid‐phase extraction purification step was performed by directly adding adsorbents into the extraction solution. The effects of various parameters on the extraction efficiency of the proposed method were investigated and optimized. Under optimum conditions, the calibration curves showed good linearity in the range of 0.25–250 (hexaconazole, diniconazole and tebuconazole), 0.5–500 (flutriafol, triadimenol and fipronil) and 0.05–200 ng g−1 (picoxystrobin) with the correlation coefficients higher than 0.9994. The limits of detection and quantification for the present method were 0.01–0.08 and 0.03–0.25 ng g−1, respectively. The recoveries of the target analytes ranged from 69.5 to 105.9%. The full procedures were applied for the preconcentration and subsequent determination of seven pesticides in four kinds of real soil samples (corn soil, herbs soil, cucumis melo soil and city lawn soil), and satisfactory results were obtained.