液相色谱-原子荧光光谱法测定稻谷中无机砷含量的不确定度评定

Uncertainty Evaluation of Determination of Inorganic Arsenic in Rice by Liquid Chromatography-Atomic Fluorescence Spectrometry

目的:对液相色谱-原子荧光光谱法测定稻谷中无机砷含量进行不确定度评定,为质量控制提供参考。方法:依据不确定度的评定原理,建立无机砷不确定度评定的数学模型,对不确定度的来源进行分析与评定,并计算合成不确定度,评定结果的扩展不确定度。结果:稻谷中无机砷的含量为(0.134±0.011)mg·kg^(-1),k=2。结论:影响无机砷含量的不确定度因素主要为标准曲线拟合,其次为样品制备、前处理过程以及稀释配制标准溶液。

Objective:To evaluate the uncertainty of the determination of inorganic arsenic in rice by liquid chromatography-atomic fluorescence spectrometry,and to provide reference for quality control.Method:According to the evaluation principle of uncertainty,a mathematical model for the evaluation of the uncertainty of inorganic arsenic was established,the source of the uncertainty was analyzed and evaluated,the combined uncertainty was calculated,and the expanded uncertainty of the result was evaluated.Result:The content of inorganic arsenic in rice was(0.134±0.011)mg·kg^(-1),k=2.Conclusion:The main uncertainty factors affecting the content of inorganic arsenic are standard curve fitting,followed by sample preparation,pretreatment process and dilution to prepare standard solution.