In this study, a combination of modified quick easy cheap effective rugged and safe extraction (QuEChERS) and dispersive liquid–liquid microextraction (DLLME) has been proposed for the extraction and preconcentration of multiclass pesticide residues from yogurt samples prior to their determination by fast gas chromatography–mass spectrometry. Factors influencing DLLME efficiency, including type and volume of extractive solvent, mixing type, salt addition, and extraction time were evaluated. The obtained extract from the first step of QuEChERS was subsequently adjusted by DLLME using tetrachloroethane as an extractive solvent. The method was fully validated within the optimized extraction parameters. The recoveries of pesticides were between 70 and 120% with relative standard deviations less than 20%. The limits of detection ranged between 0.04 ng/L and 2.00 μg/L, and the limits of quantification ranged from 0.12 ng/L to 6.60 μg/L. The optimized method was employed for the determination of pesticides in real samples of yogurts.

在这项研究中，已提出将改良的快速，简便，廉价，有效，坚固，安全的萃取物（QuEChERS）与分散液-液微萃取物（DLLME）结合使用，以从酸奶样品中提取和预浓缩多残留农药，然后再通过快速气体测定色谱-质谱联用。评估了影响DLLME效率的因素，包括萃取溶剂的类型和体积，混合类型，加盐和萃取时间。随后使用四氯乙烷作为萃取溶剂，通过DLLME调节从QuEChERS第一步中获得的提取物。该方法在优化的提取参数范围内得到了充分验证。农药的回收率在70％至120％之间，相对标准偏差小于20％。检出限为0。04 ng / L和2.00μg/ L，定量限范围为0.12 ng / L至6.60μg/ L。该优化方法用于测定酸奶实际样品中的农药。