液质联用法测定苹果中氧化乐果残留的不确定度评定

Uncertainty Evaluation for the Determination of Omethoate in Apple by Liquid Chromatography-tandem Mass Spectrometry

本文采用液相色谱质谱联用法,测定苹果中氧化乐果残留含量。对测量不确定度,建立了数学模型,分析引入因素、计算合成,进行不确定度评估。结果表明:标准物质配制、回收率和提取净化的定容等是不确定度的主要来源,也是质量控制的关键。当苹果中氧化乐果残留含量为0.018 3 mg/kg时,扩展不确定度为0.001 0 mg/kg(k=2)。

This paper aimed to evaluate the uncertainty of measurement in the determination of omethoate in apple by liquid chromatography-tandem mass spectrometry (LC-MS/MS),a mathematical model was established to analyze,calculate and synthesize the sources of uncertainty.The results showed that the evaluation process showed that the preparation of reference materials,recovery rate and constant volume of extraction and purification were the main sources of uncertainty,and the key to quality control.The expanded uncertainty was 0.001 0 mg/kg (k=2),when the content of the omethoate in apple was 0.018 3 mg/kg.