建立同位素稀释-超高效液相色谱-串联质谱法同时测定水产品中孔雀石绿、结晶紫、隐性孔雀石绿、隐性结晶紫残留的不确定度评定方法,依据GB/T 19857-2005《水产品中孔雀石绿和结晶紫残留量的测定》,建立数学模型,通过不确定度来源分析建立不确定度评价方法。结果表明:标准溶液的配制和标准曲线拟合引入的不确定度最大,而同位素稀释法可以减小前处理过程和基质效应引入的不确定度。水产品中孔雀石绿残留量为14.26 μg/kg时,其扩展不确定度为1.35 μg/kg(k=2);结晶紫残留量为15.28 μg/kg时,其扩展不确定度为1.29 μg/kg(k=2);隐性孔雀石绿残留量为14.47 μg/kg时,其扩展不确定度为1.21 μg/kg(k=2);隐性结晶紫残留量为14.69 μg/kg时,其扩展不确定度为1.24 μg/kg(k=2)。
A method for the evaluation of the uncertainty of malachite green,crystal violet,leuco malachite green and leuco crystal violet residues in aquatic products by ultra performance liquid chromatography-stable isotope dilution mass spectrometry was established. According to the determination of malachite green and crystal violet residues in aquatic product(GB/T 19857-2005),the mathematical models of uncertainty was established and the sources of uncertainty were analyzed. As a result,the main sources of uncertainty in measurement results were the preparation of standard solution and the standard curve fitting,isotope dilution method can reduce the sources of uncertainty introduced by the pretreatment process and matrix effect. The residue of MG in aquatic products was 14.26 μg/kg,the expanded uncertainty was 1.35 μg/kg(k=2). The residue of CV was 15.28 μg/kg,the expanded uncertainty was 1.29 μg/kg(k=2).The residue of LMG was 14.47 μg/kg,the expanded uncertainty was 1.21 μg/kg(k=2).The residue of LCV was 14.69 μg/kg,the expanded uncertainty was 1.24 μg/kg(k=2).