砷铈催化分光光度法测定尿中碘的不确定度评定

Evaluation of Uncertainty in Determination of Urine Iodine by Arsenic-Cerium Catalytic Spectrophotometry

目的对砷铈催化分光光度法测定尿碘进行不确定度评定。方法采用WS/T 107.1-2016方法测定尿中碘,确定不确定度的来源,量化样品测量过程中的不确定度。结果使用该法测定尿碘浓度,经过不确定度评定,由标准物质纯度、称重、体积、拟合标准曲线和样品前处理引入的不确定度分别为1.50×10-4、2.42×10-3、4.20×10-2、9.32×10-2和 1.22×10-2。结论砷铈催化分光光度法测定尿中碘的实验过程中,拟合标准曲线是不确定度的主要来源,根据大小,可以引入不确定度的其他主要因素分别为体积、样品前处理、称重、标准物质纯度。

Objective Uncertainty evaluation of Arsenic-Cerium catalytic spectrophotometric determination of urine iodine. Methods Urinary iodine was determined by the method of WS/T 107.1-2016. The sources of uncertainty were discussed in the sample measurement. Results The uncertainty introduced by the purity of reference materials, weighing, volume, standard curve and sample pretreatment were 1.50×10-4,2.42×10-3,4.20×10-2,9.32×10-2,and 1.22×10-2, respectively. Conclusion In the experimental process of the determination of iodine in urine by arsenic-cerium catalytic spectrophotometry, the fitting standard curve is the main source of uncertainty. According to their components, the uncertainty introduced by other factors is volume, sample pretreatment, weighing and Standard Material’s purity.