基于QuEChERS-气相色谱-质谱联用技术测定海产制品中亚硝胺的不确定度评估

Uncertainty evaluation of N-dimethyl nitrosamine in marine products based on QuEChERS and gas chromatography-mass spectrometry

中文关键词:  气相色谱-质谱联用法  QuEChERS  N-二甲基亚硝胺  海产品  不确定度

英文关键词:gas chromatograph mass spectrometer  QuEChERS  N-dimethyl nitrosamine  marine products  uncertainty

中文摘要:

      目的 对QuEChERS-气相色谱-质谱联用法(gas chromatography-mass spectrometry, GC-MS)内标定量测定海产制品中亚硝胺残留量的方法进行不确定度评估。方法 根据CNAS-GL006: 2019《化学分析中不确定度的评估指南》, 分析QuEChERS-气相色谱-质谱联用内标定量法检测海产制品中亚硝胺实验过程的不确定度来源, 建立样品中N-二甲基亚硝胺不确定度评定的数学模型, 从测定方法分析并简化不确定度来源, 计算合成不确定度和扩展不确定度。结果 QuEChERS-气相色谱-质谱联用法测定水中亚硝胺的不确定度主要有6个来源: 配制系列标准溶液引入的不确定度, 样品前处理引入的不确定度, 样品重复性测量引入的不确定度, 工作曲线拟合引入的不确定度, 加标回收测定引入的不确定度, 检测仪器本身引入的不确定。当测定海产品中亚硝胺含量为24.46 μg/kg时, 扩展不确定度为2.08 μg/kg。结论 本方法适用于QuEChERS-气相色谱-质谱联用内标定量法测定海产制品中亚硝胺残留量的不确定度分析, 为科学评价基因毒性物质残留测量结果质量提供了依据。

英文摘要:

      Objective To evaluate the uncertainty of the internal standard method for quantitative determination of nitrosamine residues in marine products by QuEChERS and gas chromatography-mass spectrometry (GS-MS). Methods According to the CNAS-GL006:2019 Evaluation guide for uncertainty in chemical analysis, the sources of uncertainty for determination of N-dimethyl nitrosamine in marine products by QuEChERS and gas chromatography-mass spectrometry combined with internal standard quantitative method were analyzed. According to set up the mathematical model for the uncertainty evaluation, it confirmed and simplified the source of uncertainty from the determination method, as well as calculated the combined uncertainty and the expanded uncertainty. Results The six main sources of the uncertainty of standard samples in the determination of nitrosamines in water by QuEChERS GC-MS were the umcertainty in the preparation of series of standard solutions, the uncertainty in sample pretreatment, the uncertainty in the measurement of sample repeatability, the uncertainty in linear and regression variance, the uncertainty in the measurement of spiked recovery, and the uncertainty in the deterction instrument itself. The content of N-dimethyl nitrosamine in seafood was 24.46 μg/kg, the expanded uncertainty was 2.0 μg/kg. Conclusion This method is suitable for the uncertainty evaluation of the determination of nitrosamine residues in marine products by QuEChERS-GC-MS internal standard quantitative method. It provides a basis for scientific evaluation of the quality of genotoxic substance residue measurement results.