原子吸收光谱法测定鱼油中镉的不确定度评定

Evaluation of Uncertainty of Measurement for Cadmium from Fish Oil by Atomic Absorption Spectrometry

目的建立测定鱼油中镉不确定度的评定方法。方法根据《测量不确定度评定与表示》的有关规定,参考《化学分析中不确定度的评估指南》,采用石墨炉原子吸收光谱法测定鱼油中镉含量并分析与评定其不确定度。结果合成标准不确定度0.20μg/kg,扩展不确定度0.40μg/kg。结论运用此不确定度评定方法控制测量过程中的关键步骤,严格按照操作规范,可有效地减低引入的不确定度,使测定结果更可靠。

Objective To establish a method for the uncertainty evaluation of measurement of cadmium from fish oil. Methods According to the relevant regulation of Evaluation and Expression of Uncertainty in Measurement and referring to Guidance on Evaluating the. Uncertainty in Chemical Analysis, the content of cadmium from fish oil was measured by the graphite furnace atomic absorption spectrometry, and the uncertainty was analyzed and evaluated. Results The combined relative standard uncertainty was 0.20 μg/kg, the expanded uncertainty was 0.40 μg/kg. Conclusion By using the method of uncertainty evaluation, the key procedure can be found and controlled in the process of measurement. The operation under the specifications during measuring process can reduce the uncertainty and make the determination results more reliable.