电感耦合等离子质谱法测定蟹黄中4种重金属含量的不确定度评定

采用电感耦合等离子质谱(inductively couple plasma mass spectrometer,ICP-MS)法测定蟹黄中4种重金属并评估该方法的不确定度。根据相关规定,建立了数学模型,分析不确定的来源,合成各不确定度分量。结果显示,铅、砷、镉和铬的扩展不确定度分别为0.040、0.010、0.048、0.064 mg/kg(包含因子k=2)；不确定的来源主要为标准溶液配制、样品前处理和标准曲线拟合。本文方法简单客观,能对ICP-MS法测定蟹黄中4种重金属含量的不确定度来源和影响因素进行分析,对提高检测的准确度和减少不确定引入的影响具有一定的效果。

Uncertainty evaluation for determination of four heavy metal content in crab roe by inductively coupled plasma mass spectrometry

Four kinds of heavy metals in crab roe were determined by inductively coupled plasma mass spectrometer (ICP-MS) and the uncertainty of this method was evaluated. According to the relevant regulations, the mathematical model was established, the source of uncertainty was analyzed and the each component of uncertainty was synthesized. It was stated that the expanded uncertainty of lead, arsenic, cadmium and chromium were 0.040, 0.010, 0.048 and 0.064 mg/kg (including factor k=2). The main sources of uncertainty comes from the standard solution preparation, the sample pretreatment and the standard curve fitting. The method is simple and objective, and can analyze the source and influencing factors of the uncertainty of the determination of four kinds of heavy metals in crab roe by ICP-MS. It has effect on improving the accuracy of detection and reducing the influence of the introduction of uncertainty.