Yan Mengmeng, Xie Yujie, Shi Mengjie, Wu Xingqiang, Tong Kaixuan, Chang Qiaoying, Chen Hui
Chinese Academy of Quality and Inspection &Testing, Beijing 100176, China.
College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
Anal Methods. 2025 Sep 18;17(36):7301-7312. doi: 10.1039/d5ay00950b.
In this study, a modified QuEChERS method for the simultaneous determination of 73 pesticides, 23 PCBs and 16 PAHs in wheat was developed by gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS). The sample was first hydrated with 4 mL of ultrapure water, extracted with 10 mL of acetone-hexane (1 : 1, V:V), and then cleaned up with a mixture of 50 mg of PSA, 150 mg of C18, and 400 mg of anhydrous MgSO. Under the optimized conditions, the samples were analyzed by GC-MS/MS for quantitative analysis using the matrix-matched external standard method. As a result, 112 compounds showed good linearity in their linear ranges with correlation coefficients () greater than 0.995, and the limits of detection (LODs) of the method were in the range of 0.15-3 μg kg, and the limits of quantification (LOQs) were between 0.5 and 10 μg kg. The recoveries ranged from 71.2% to 112.1%, with relative standard deviations (RSD, = 6) below 20% at the three spiked levels (LOQ, 2× LOQ, and 10× LOQ). The intra-day precision and inter-day precision were within 0.5-11.6% and 2.4-18.9%, respectively. The proposed method was applied to 40 batches of wheat samples, and neither PCBs nor PAHs were detected. Five pesticides were detected: epoxiconazole, difenoconazole, flutriafol, bifenthrin, and simazine. Among them, simazine was detected in 10 batches of samples, with concentrations ranging from 10.01 to 48.31 μg kg, which exceeded the MRL prescribed by the EU. The results demonstrate that the method is characterized by simple pretreatment, rapidity, and sensitivity, and is suitable for the simultaneous determination of pesticide residues and environmental pollutants in wheat.
在本研究中，建立了一种改进的QuEChERS方法，用于通过气相色谱 - 三重四极杆串联质谱（GC-MS/MS）同时测定小麦中的73种农药、23种多氯联苯和16种多环芳烃。样品首先用4 mL超纯水水化，用10 mL丙酮 - 己烷（1∶1，V∶V）萃取，然后用50 mg PSA、150 mg C18和400 mg无水硫酸镁的混合物净化。在优化条件下，采用基质匹配外标法通过GC-MS/MS对样品进行定量分析。结果表明，112种化合物在其线性范围内具有良好的线性，相关系数（）大于0.995，该方法的检测限（LOD）在0.15 - 3 μg/kg范围内，定量限（LOQ）在0.5至10 μg/kg之间。回收率在71.2%至112.1%之间，在三个加标水平（LOQ、2×LOQ和10×LOQ）下相对标准偏差（RSD， = 6）低于20%。日内精密度和日间精密度分别在0.5 - 11.6%和2.4 - 18.9%范围内。所提出的方法应用于40批次小麦样品，未检测到多氯联苯和多环芳烃。检测到5种农药：环氧唑菌唑、苯醚甲环唑、粉唑醇、联苯菊酯和西玛津。其中，在10批次样品中检测到西玛津，浓度范围为10.01至48.31 μg/kg，超过了欧盟规定的最大残留限量。结果表明，该方法具有预处理简单、快速、灵敏的特点，适用于同时测定小麦中的农药残留和环境污染物。
