氢化物原子荧光法测定尿中砷的不确定度分析

Uncertainty Evaluation on the Determination of Arsenic in Urine by Hydride Generation Atomic Fluorescence Spectrometry

目的建立用氢化物发生原子荧光法测量尿中砷的不确定度评定方法。方法依据《尿中砷的测定氢化物发生原子荧光法》(WS/T 474-2015)和《测量不确定度评定与表示》(JJF 1059.1-2012),建立尿中砷测定的数学模型,计算各分量引入的不确定度。结果尿中砷的测量不确定度的主要来源依次是最小二乘法拟合校准曲线所产生的不确定度(1.85%)、回收率所产生的不确定度(1.28%)以及样品重复测定的不确定度(0.87%)。结论通过对尿中砷含量进行测量不确定度评定和分析,将有助于检测人员对试验过程关键环节重点关注,使检测数据更加真实可靠。

Objectives To established the uncertainty evaluation method for determination of arsenic in urine by hydride atomic fluorescence spectrometry. Methods Determination of arsenic in urine by hydride generation atomic flurescence spectrometry（ WS/T 474-2015） and evaluation and expression of uncertainty in measurement（ JJF1059. 1-2012） were utilized to build mathematical model of arsenic in urine. Results The study showed that the least squares fitting calibration curve（ 1. 85%）,the rate of recovery（ 1. 28%） and the repeated measurements（ 0. 87%） were key factors influencing the reliability of result from determination of arsenic in urine. Conclusions The uncertainty assessment method will identify the key links in the process of measurement and make the result more reliable.