QuEChERS-超高效液相色谱-串联质谱法测定牛奶中壬基酚残留量方法及不确定度评定

Determination of nonylphenol in milk by QuEChERS-ultra high performance liquid chromatography–tandem mass spectrometry and the evaluation of the uncertainty

中文关键词:  壬基酚  牛奶  超高效液相色谱-串联质谱法  测量不确定度

英文关键词:nonylphenol  milk  ultra high performance liquid chromatography-tandem mass spectrometry  measurement uncertainty

中文摘要:

      目的 建立超高效液相色谱-串联质谱法测定牛奶中壬基酚残留量, 并评定其不确定度。方法 分析基质效应, 比较不同流动相的分析效果, 对分析主要的试剂的目标物残留量, 优化超高效液相色谱-串联质谱仪条件。并根据CNAS-GL 006:2018及JJF 1059.1-2012, 评定不确定度。结果 牛奶基质会产生很大的基质抑制效应, 该方法检出限为0.1 μg/kg, 回收率为85.7%~110.9%, 精密度为4.9%~9.5%, 相关系数≥0.9990。本研究建立了不确定度评价的数学模型, 最后扩展相对标准不确定度为0.072, 残留量可表示为C=(11.33±0.82) μg/kg, k=2。结论 本方法操作简便、检出限低、灵敏度高、满足方法学要求, 适用于牛奶中壬基酚的测定。通过不确定度各分量分析, 其中测量重复性、标准品和标准曲线拟合是对测量不确定度的最重要来源。

英文摘要:

      Objective To establish a method for the determination of nonylphenol in milk samples by ultra high performance liquid chromatography-tandem mass spectrometry and estimate of the measurement uncertainty. Methods The matrix effect was analyzed, the analysis effect of different mobile phases was compared, the target residues of main reagents were analyzed, and the conditions of ultra-high performance liquid chromatography-tandem mass spectrometer were optimized. The uncertainty was assessed according to CNAS-GL 006:2018 and JJF 1059.1?2012. Results The matrix inhibition effect of milk was very large, and the limit of detection this method was 0.1 g/kg.The recoveries were 85.7%?110.9%, the precision were 4.9%?9.5%, and the correlation coefficient was≥0.9990. In this study, a mathematical model for the evaluation of uncertainty was established, and the extended relative standard uncertainty was 0.072. The residual amount could be expressed as C=(11.33±0.82) g/kg, k=2. Conclusion This method is simple and rapid, the sensitivity, precision and recovery are all satisfied with the methodological requirements, which can be suitable for determination of nonylphenol in milk samples. The repeated measurement, standard substance itself and curve are the important sources of measurement uncertainty.