气相色谱-串联质谱法测定柑橘中苯醚甲环唑的不确定度评定

Uncertainty Evaluation on Determination of Difenoconazole in Citrus byGas Chromatography-Mass Spectrometry

本文运用气相色谱-串联质谱法对柑橘中苯醚甲环唑残留量进行测定,建立数学模型,分析测定过程的主要不确定度来源,对不确定度各个分量进行评估。结果表明,测量不确定度主要来源于前处理方法提取和净化产生的回收率差异、标准溶液配制和目标物色谱峰面积测定误差。当苯醚甲环唑的残留量为0.047 mg/kg时,扩展不确定度为0.003 mg/kg(P=95%,k=2)。

This paper used gas chromatography-mass spectrometry to determine the difenoconazole residues in citrus,established a mathematical model,analyzed the main sources of uncertainty in the determination process,and evaluated each uncertainty component.The results showed that the measurement uncertainty mainly came from the difference in the recovery rate of the extraction and purification in the pretreatment method,the preparation of the standard solution and the measurement error of the target chromatographic peak area.When the residual amount of difenoconazole was 0.047 mg/kg,the expanded uncer-tainty was 0.003 mg/kg(P=95%,k=2).