液相色谱-电感耦合等离子体质谱联用法测定鱼类干制品中甲基汞含量的测量不确定度评估

Uncertainty evaluation of determination for determining the content of methylmercury in dried fish products by liquid chromatography-inductively coupled plasma mass spectrometry

液相色谱—电感耦合等离子体质谱法测定鱼类干制品中的甲基汞含量,分析测定过程,评估重复测量、样品称量、前处理、标准溶液、标准曲线拟合等方面的测量不确定度。结果发现测量过程中对结果影响较大的因素主要是标准溶液纯度及配制、标准曲线拟合,重复测量。可能由于该样品是用于新方法开验样品之一,实验人员对实验过程控制严格,同时样品中甲基汞含量较低导致,但作为日常检测中测量不确定度主要来源的测量重复性不容忽视,日常检测工作的开展应重点关注这些方面。

Liquid chromatography-inductively coupled plasma mass spectrometry was used to determine the content of methylmercury in dried fish products,and the determination process was analyzed,and uncertainty evaluation of determination such as repeated determination,sample weighing,pretreatment,standard solution,standard curve fitting and others were evaluated.The results showed that the main factors affecting the results during the determination process were the purity and preparation of the standard solution,the fitting of standard curve and repeated measurements.It might be due to the fact that this sample was one of the samples used for the new method,and the experimental process was strictly controlled by experimenter,and the content of methylmercury in the sample was low,but the determination repeatability,which was the main source of determination uncertainty in daily testing,could not be ignored,and these aspects should be focused when the daily testing work was conducted.