高效液相色谱法测定蔬菜中异菌脲残留量的不确定度分析

采用高效液相色谱法对蔬菜中异菌脲残留量的不确定度进行评估。根据JJF 1135—2005《化学分析测量不确定度评定》和JJF 1059.1—2012《测量不确定度评定与表示》中的有关规定,建立测定蔬菜中异菌脲残留量不确定度的数学模型,逐层对不确定度来源进行分析。通过对不确定度分量进行量化和合成,得出当蔬菜中异菌脲残留量为5.31 mg/kg时,其扩展不确定度为0.40 mg/kg(k=2)。结果表明,影响检测结果的主要因素为标准溶液配制、标准曲线拟合和测量重复性等。

Uncertainty Evaluation for the Determination of Iprodione Residues in Vegetables by High Performance Liquid Chromatography

The uncertainty of measurement in the determination of iprodione residues in vegetables by high performance liquid chromatography (HPLC) was evaluated. According to the national metrology technical specifications JJF 1135-2005 (Evaluation of Uncertainty in Chemical Analysis Measurement) and JJF 1059.1-1999 (Evaluation and Expression of Uncertainty in Measurement), a mathematical model was established to evaluate the uncertainty for determining iprodione residues in vegetables. The sources of uncertainty that may be introduced were analyzed and each component of uncertainty was quantified and used to calculate combined uncertainty. The results showed that an expended uncertainty of 5.31 mg/kg (k = 2) was obtained for the determination of 0.40 mg/kg of iprodione in vegetables, and the preparation of standard solution, calibration curve fitting and measurement repeatability were the main sources of uncertainty.