豆腐皮中乌洛托品残留量的测定不确定度评估

目的评定液相色谱-质谱法测定豆腐皮中乌洛托品留量的不确定度。方法运用JJF 1059.1-2012《测量不确定度评定与表示》分析豆腐皮中的乌洛托品残留量测量过程中的不确定度来源,通过建立数学模型量化不确定度分量,计算合成不确定度和扩展不确定度。结果本方法的不确定度主要来源于液相色谱质谱仪设备。当豆腐皮中乌洛托品残留量为0.523 mg/kg,扩展不确定度为0.018 mg/kg,乌洛托品残留量表示为(0.523±0.018)mg/kg(k=2)。结论该评定方法可为液相色谱-质谱法测定豆腐皮中乌洛托品残留量的结果和方法的可靠性提供科学依据。

Evaluation of uncertainty in determination of urotropine in Tofu skin

Objective To evaluate the uncertainty in determination of urotropine in Tofu skin by liquid chromatography-mass spectrometry (LC-MS). Method According to JJF 1059.12-2012 Evaluation and expression of uncertainty in measurement, the uncertainty sources in determination of urotropine in Tofu skin were analyzed. Furthermore, the combined uncertainty and expanded uncertainty were calculated based on the established mathematic models. Results The major uncertainty source in this method was liquid chromatography-mass spectrometer equipment. When the urotropine residual content in Tofu skin was 0.523 mg/kg, the expanded uncertainty was 0.018 mg/kg, and the urotropine residual content was expressed as (0.523±0.018) mg/kg (k=2). Conclusion The method can provide a scientific basis for the measurement results and the reliability of the method of liquid chromatography-mass spectrometry for the determination of urotropine residual in Tofu skin.