电感耦合等离子体质谱法测定肉制品中总砷的不确定度评定

Evaluation of uncertainty determination of total arsenic in meat products by inductively coupled plasma mass spectrometry

中文关键词:  不确定度  电感耦合等离子体质谱法  总砷  肉制品

英文关键词:uncertainty  inductively coupled plasma mass spectrometry  total arsenic  meat products

中文摘要:

      目的 评定电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry, ICP-MS)测定肉制品中总砷含量的不确定度。方法 依据CNAS-GL06:2006 《化学分析中不确定度的评估指南》和JJF 1135-2005 《化学分析测量不确定度评定》, 通过建立不确定度数学模型, 采用微波消解-ICP-MS测定肉制品中的总砷含量, 分析该方法测量不确定度的主要来源, 并评定各标准不确定度的分量。结果 在肉制品的总砷含量测定中, 当样品的总砷含量为0.120 mg/kg, 其扩展不确定度为0.008 mg/kg (k=2), 结果表示为(0.120±0.008) mg/kg。结论 用ICP-MS进行测量时, 主要不确定度来源于样品的重复性测定、标准物质及配制、标准曲线拟合, 通过降低可控不确定度来提高测量结果的准确度, 该质量控制手段可用于合理地体现测定结果的可靠程度。

英文摘要:

      Objective To evaluate the uncertainty of determination of total arsenic content in meat products by microwave digestion-inductively coupled plasma mass spectrometry (ICP-MS). Methods According to CNAS-GL06:2006 Guidance on evaluating the uncertainty in chemical analysis and JJF 1135-2005 Evaluation of uncertainty in chemical analysis measurement, the mathematical model of uncertainty was established, and the total arsenic in meat products was measured by microwave digestion-ICP-MS. Then the main sources of uncertainty in this method were analyzed and the components of uncertainty of each standard were evaluated. Results In the determination of total arsenic content in meat products, when the total arsenic content of meat products was 0.120 mg/kg, the extended uncertainty was 0.008 mg/kg (k=2), and the result was (0.120±0.008) mg/kg. Conclusion The main uncertainties of determination of total arsenic in meat products by ICP-MS are the repeatability of samples, standard substance and preparation, and standard curve fitting. By reducing the degree of controllable uncertainty to improve the accuracy of the measurement results, the quality control method can be used to show the reliability of the results.