QuEChERS-气相色谱-串联质谱法测定结球甘蓝中甲基毒死蜱农药残留不确定度评估

目的对QuEChERS-气相色谱-串联质谱法测定结球甘蓝中甲基毒死蜱农药残留进行不确定度评估。方法运用气相色谱-串联质谱法对结球甘蓝中甲基毒死蜱残留量进行测定,通过建立数学模型,分析测定过程的主要不确定度来源,对各个分量进行评估。结果不确定性的主要来源是标准溶液的配制、工作曲线的拟合及加标回收率引入。当甲基毒死蜱的残留量为0.041 mg/kg时,扩展不确定度为0.003 mg/kg (k=2)。结论该方法适用于气相色谱-串联质谱法测定甲基毒死蜱残留量的不确定度分析,可为农药残留测量结果的准确性提供科学可靠的依据。

Uncertainty evaluation for determination of chlorpyrifos-methyl residues in cabbage by QuEChERS-gas chromatography- tandem mass spectrometry

Objective The study was aimed at uncertainty evaluation for determination of chlorpyrifos-methyl Residues in Cabbage by QuEChERS-gas chromatography-mass spectrometry. Methods The residue of chlorpyrifos methyl in cabbage was determined by gas chromatography tandem mass spectrometry. Through the establishment of mathematical model, the main sources of uncertainty in the measurement process were analyzed, and each component was evaluated. Results The results show that the main sources of uncertainty arose from the preparation of standard solution, the fitting of working curve and the recovery rate of standard addition. When the residue of chlorpyrifos-methyl was 0.041 mg/kg, the expanded uncertainty was 0.003mg/kg (k = 2). Conclusion This method is suitable for the uncertainty analysis of chlorpyrifos methyl residue by gas chromatography tandem mass spectrometry, and can provide scientific and reliable basis for the accuracy of pesticide residue measurement results.