稳定性同位素稀释气相色谱-质谱法测定白酒中DBP、DEHP含量及不确定度评定  

Determination of DBP and DEHP Content in Baijiu(Liquor) by Stable Isotope Dilution GC-MS and Evaluation on Its Uncertainties

作　　者：李凤华[1] 李蔚[1] 曹艳平[1] 

机构地区：[1]山东省疾病预防控制中心,山东济南250014

出　　处：《酿酒科技》2014年第10期111-115,共5页Liquor-Making Science & Technology

摘　　要：采用稳定性同位素稀释气相色谱-质谱法对白酒中DBP、DEHP的含量进行测定,并对整个测试过程的不确定度来源进行系统分析。样品提取、离心后取上层有机相进行测定,利用选择离子监测模式,以氘代同位素标记物作内标,以m/z 149和m/z153为定量离子对,对其定性定量测定,并对测试过程中引入的各个分量进行评定与合成。结果表明,DBP、DEHP在0.2-2.0 mg/L浓度范围内线性关系良好,r≥0.999,定量限为0.05 mg/kg,不同加标水平中的平均回收率为DBP：91.2%-100.4%,RSD为2.24%-2.79%（n=5）;DEHP：99.0%-110.6%,RSD为4.98%-5.44%（n=5）。当DBP测定结果为0.572 mg/kg时,扩展不确定度为0.040 mg/kg,DEHP测定结果为0.251 mg/kg时,扩展不确定度为0.025 mg/kg,k=2,p=95%。该方法准确可靠,可用于白酒中DBP、DEHP的含量测定。并且建立的不确定度评定方法可用于气相色谱-质谱法测定白酒中DBP、DEHP浓度的不确定度评估。标准溶液配制和标准曲线拟合、样品前处理以及分析仪器是主要的不确定度来源。In this study, DBP and DEHP content in Baijiu（liquor） was determined by stable isotope dilution GC-MS, and the uncertainties source in the determination process was analyzed systematically. In the operation process, after liquor sample extraction and centrifugation, the upper-layer organic phase was determined by GC-MS with m/z149 and m/z153 as the quantitative ion pair in selective ions monitoring mode and deuterium isotope used as the internal standards, and each component introduced in the determination process was evaluated and synthesized. The experimental results showed that, DBP and DEHP presented a good linear relationship within the range of 0.2 -2.0 mg/L with r ≥0.999,LOQ= 0.05 mg/kg, the average recoveries of DBP between 91.2 % to 100.4 % and its RSD with the range of 2.24 %-2.79 %（n=5）, and the average recoveries of DEHP between 99.0 % to 110.6 % and its RSD within the range of 4.98 %-5.44 %（n=5）. As the determination results of DBP and DEHP were 0.572 mg/kg and 0.251 mg/kg, their expanded uncertainties were 0.040 mg/kg and 0.025 mg/kg respectively（k=2,p=95 %）. Such method was suitable for the determination of DBP and DEHP content in Baijiu（liquor）. The uncertainties source in the determination mainly came from the preparation of standard solution, standard curve fitting, pretreatment of liquor samples and the analytical instrument.

关 键 词：气相色谱-质谱(GC-MS) DBP DEHP 同位素稀释 不确定度 白酒 

分 类 号：O657.63[理学—分析化学] TS262.3[理学—化学]