UPLC-MS法测定肉制品中虾过敏原含量的不确定度评定OACSTPCD

The uncertainty for the determination of shrimp allergen contents in meat products by ultra high performance liquid chromatography tandem mass spectrometry(UPLC-MS)was evaluated using a new mathematical model.Specifically,our equations could be applied to calculate each individual uncertainty component,as well as the synthetic uncertainty,and ultimately to generate the extended uncertainty.The uncertainty during the UPLC-MS measurement usually came from the following sources:sample weighing,repeatability test,method accuracy,sample pretreatment process,and sample solution determination process.Among these sources,the sample solution determination process counted the most for the uncertainty,especially from the standard curve fitting and reference sample weighing process.In our case,the relative synthetic standard uncertainty turned out to be 0.057 9,with the actual synthetic standard uncertainty as 1.21 mg/kg.Based on the expansion factor k=2 for the confidence at 95％level,the relative expansion uncertainty and actual expansion uncertainty during the measurement of shrimp allergen contents in meat products could be accordingly obtained as 0.116,and 2.42 mg/kg,respectively.According to the contribution of each uncertainty component,the sample weight of the reference substance and the concentration range for the working solution of the standard curve proved to be two key factors for the reduction of overall uncertainty.It is highly recommended that the uncertainty value should be provided whenever the analytical results are reported for the content determination of actual samples.