超高效液相色谱-串联质谱法测定水果罐头中乙二胺四乙酸二钠含量和不确定度评价

Determination of ethylenediaminetetraacetic acid disodium in canned fruit by using ultra-performance liquid chromatography–tandem mass spectrometry and uncertainty evaluation

目的 建立超高效液相-质谱/质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)测定水果罐头中的乙二胺四乙酸二钠(ethylenediaminetetraacetic acid disodium,EDTA-2Na)的分析方法 并进行不确定性评价.方法分析采用Phenyl柱(50 mm×2.1 mm,1.7μm);流动相A为0.02 mol/L乙酸铵,流动相B为甲醇,流动相流速:0.2 mL/min,柱温:40℃,梯度洗脱;电喷雾离子源负离子扫描(electron spray ionization,ESI),选择多反应监测模式检测(multi reaction monitoring,MRM).通过数学模型的建立,分析测量不确定度的来源,并量化各个不确定度分量,最终合成不确定度.结果 EDTA-2Na在0.2~25 mg/L时呈现良好的线性关系,相关系数r2为0.995377,加标回收率为83.5%~94.1%,相对标准偏差(relative standard deviation,RSD)为0.350%~0.772%.水果罐头中EDTA-2Na含量测定的合成不确定度为2.14%,测量结果为(68.8±2.94)mg/kg.结论 不确定度主要由标准溶液、样品处理过程中的标准曲线的建立及样品加标回收引起.本研究为UPLC-MS/MS法测定食品中EDTA-2Na的含量及进行不确定度评价提供了参考.

Objective To establish a method for the determination of ethylenediaminetetraacetic acid disodium(EDTA-2 Na) in canned fruit by ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) and evaluate the uncertainty. Methods Phenyl column(50 mm ×2.1 mm, 1.7 μm) was used for analysis. Mobile phase A was 0.02 mol/L ammonium acetate, mobile phase B was methanol, mobile phase flow rate was 0.2 mL/min, column temperature was 40 ℃, and gradient elution was performed. The detection was electrospray ion source negative ion scan(ESI) and the multi reaction monitoring mode detection(MRM). Through the establishment of mathematical model, the sources of measurement uncertainty were analyzed, each measurement uncertainty components were quantified, and finally the uncertainty was synthesized. Results EDTA-2 Na presented a good linear relationship at 0.2-25 mg/L, the correlation coefficient was 0.995377, the standard recovery was 83.5%-94.1%, and the relative standard deviation was 0.350-0.772%. The uncertainty of synthesis of EDTA-2 Na in canned fruit was 2.14%, and the measurement result was(68.8±2.94) mg/kg. Conclusion The uncertainty is mainly caused by standard solution, the establishment of the standard curve during sample processing and the recycling of the labeled sample. This study provides a theoretical basis for using UPLC-MS/MS method determine EDTA-2 Na in food and uncertainty evaluation.