高效液相色谱-质谱/质谱联用法测定鸡蛋中氯霉素残留量的不确定度评定

HPLC-MS/MS Uncertainty Evaluation in Determination of Chloramphenicol Residues in Eggs

对高效液相色谱-质谱/质谱联用法检测鸡蛋中氯霉素残留的测量不确定度进行评定。参照GB/T 22338-2008中的液相色谱-质谱/质谱法检测鸡蛋样品,依据测量不确定度评定的相关指导文件建立了不确定度数据模型,分析了检测过程中可能引入的不确定度来源,并算出测量结果的合成标准不确定度和扩展不确定度。当鸡蛋样品中残留量为0.493μg·kg^(-1)时,其扩展不确定度为U=0.020 3×2=0.040 6μg·kg^(-1),氯霉素残留量为(0.493±0.0406)μg·kg^(-1)(k=_2)。实验过程中引入的不确定度对检测结果影响较大的主要有标准物质配制、样品重复测定、标准曲线拟合以及仪器定量校准;而标准物质称量、样品称重质量、最终定容体积以及样品回收率等引入的不确定度分量对检测结果影响相对较小。

The uncertainty of determination of chloramphenicol residues in eggs by high performance liquid chromatography-tandem mass spectrometry was evaluated. Referring to the standard GB/T 22338-2008, egg samples were detected by liquid chromatography-mass spectrometry/mass spectrometry. The uncertainty data model was established according to the relevant guidance documents for evaluation of measurement uncertainty. The sources of uncertainty that may be introduced in the detection process were analyzed, and the synthetic standard uncertainty and expanded uncertainty of measurement results were calculated. When the residue in eggs was 0.493 ug/kg, the expanded uncertainty was U=0.020 3×2=0.040 6 μg·kg^-1, and the result of chloramphenicol residue was (0.493±0.040 6)μg·kg^-1 (k=2). The main components of uncertainty introduced in the experiment process have great influence on the test results, such as the preparation of reference materials, repeated determination of samples, standard curve fitting, instrument quantitative calibration;while the uncertainty components introduced in the process of reference materials weighing, sample weighing quality, final volume, sample recovery rate have relatively small influence on the test results.