液相色谱串联质谱内标法测定猪肉中沙丁胺醇及莱克多巴胺残留量的不确定度分析

Uncertainty evaluation for the determination of salbutamol and ractopamine residues in pork by liquid chromatography with tandem-mass spectrometric internal standard method

目的对液相色谱串联质谱内标法测定猪肉中沙丁胺醇、莱克多巴胺2种β-受体激动剂残留量的不确定度进行分析。方法采用液相色谱串联质谱以沙丁胺醇D3为内标对猪肉中沙丁胺醇、莱克多巴胺2种β-受体激动剂残留量进行测定;建立数学模型,对测量重复性、标准物质纯度、标准溶液配制、内标物质添加、仪器进样体积等不确定因素进行评定。结果当猪肉中沙丁胺醇、莱克多巴胺残留量分别为11.004μg/kg和11.770μg/kg时,其扩展不确定度分别为2.628μg/kg和2.839μg/kg(k=2)。结论标准曲线拟合过程、仪器进样体积、标准系列配制过程对检测结果影响最大。

Objective To analyze the uncertainty for the determination of salbutamol and ractopamine in pork by liquid chromatography tandem-mass spectrometry internal standard method.Methods The uncertainty for the determination of salbutamol and ractopamine in pork was analyzed by liquid chromatography tandem-mass spectrometry with salbutamol-D3 as internal standard.The mathematical model was established to evaluate the uncertainty factors such as measurement repeatability,purity of standard substances,preparation of standard solution,addition of internal standard substances and volume of sample injection.Results When the residual amounts of salbutamol and ractopamine in pork were 11.004μg/kg and 11.770μg/kg respectively,the extended uncertainty was 2.628μg/kg and 2.839μg/kg respectively(k=2).Conclusion The standard curve fitting process,the volume of instrument injection and the standard series preparation process have the greatest influence on the test results.