目的评定液相色谱-串联质谱检测对虾中T-2毒素的不确定度。方法样品经乙酸乙酯提取,无水硫酸钠脱水,提取上清液氮气吹干后用1 mL 0.1%甲酸的甲醇:水溶液(3:7,V:V)定容,正己烷除脂。基质匹配法定量。液相采用甲醇和0.1%甲酸酸化的5 mmol/L乙酸铵溶液梯度洗脱,质谱采用电喷雾离子化方式下正离子的选择离子监测模式对T-2毒素的定量离子和定性离子进行监测。通过分析并计算检测过程中各不确定度分量得到合成标准不确定度。结果本方法检测T-2毒素的合成标准不确定度为0.739μg/kg,取置信概率95%的扩展不确定度为1.5μg/kg。所以,试样中T-2毒素的测量结果为:X=(12.7±1.5)μg/kg,k=2。结论此检测方法使外标法的定量结果更为真实有效,方法不确定度的评定亦可为采用空白基质匹配法的现行相关检测方法的不确定度评估提供参考。 Objective To assess the uncertainty of detection of T-2 toxin in shrimp by liquid chromatography-tandem mass spectrometry. Methods The sample was extracted with ethyl acetate, dehydrated with anhydrous sodium sulfate, the supernatant was extracted with nitrogen and dried with 1 mL of 0.1% formic acid in methanol: water (3: 7, V: V). Matrix matching method to quantify. The liquid phase was eluted with a gradient of 5 mmol / L ammonium acetate in methanol and 0.1% formic acid, and the quantitative ion and qualitative ions of T-2 toxin were monitored by mass spectrometry with selective ion monitoring of positive ions under electrospray ionization. The synthetic standard uncertainty is obtained by analyzing and calculating the components of each uncertainty in the detection process. Results The standard uncertainty for the determination of T-2 toxin in this method was 0.739 μg / kg, and the extended uncertainty of 95% confidence interval was 1.5 μg / kg. Therefore, the measurement of T-2 toxin in the sample is: X = (12.7 ± 1.5) μg / kg, k = 2. Conclusion This method makes the quantitative results of the external standard method more true and effective. The evaluation of the method uncertainty can also provide a reference for the evaluation of the uncertainty of the relevant detection methods using the blank matrix matching method.