电感耦合等离子体质谱法测定水产品中16种元素的不确定度评定

摘要

Objective To analyze the uncertainty of 16 kinds of elements in aquatic products by inductively coupled plasma mass spectrometry (ICP-MS).Methods According to the actual situation and JJF 1059.1-2012 Measurement uncertainty evaluation and representation, the uncertainty factors affecting the results were analyzed. Combined with the analysis of the sample quality, volume, curve fitting, measurement repeatability and other factors on the uncertainty model of influence degree of components, the uncertainty was evaluated.Results The relative expanded uncertainty of each element was in the range of 1.89%~7.81%, which could meet the requirement of normal work.The uncertainty mainly came from 2 aspects: the fitting of the standard curve and the repeatability of the sample pretreatment. In order to reduce the uncertainty of standard solution curve fitting, the quality and concentration of internal standard elements could be changed.ConclusionThis method accurately reflects the confidence and accuracy of the measurement, and provides reference for the daily actual inspection work.%目的：采用电感耦合等离子质谱法对水产品中16种元素的不确定度进行分析。方法根据实验过程中变量因素并结合JJF 1059.1-2012《测量不确定度评定与表示》的有关规定，分析影响各元素结果的不确定度因素，结合分析样品称样质量、定容体积、曲线拟合、仪器测量重复性等因素对不确定度分量的影响建立模型，并对不确定度进行了评估。结果各元素的相对扩展不确定度在1.89%~7.81%之间，满足正常的工作需求。不确定度主要来源于标准曲线的拟合和样品前处理的重复性两方面，可通过改变内标元素的质量数和浓度等因素以降低标准溶液曲线拟合引入的不确定度。结论本方法如实反映测量的置信度和准确性，为日常实际检验工作提供参考。