气相色谱-质谱法测定葡萄酒用软木塞中2,4,6-三氯苯甲醚的不确定度评定

Uncertainty evaluation for the determination of 2,4,6-trichloroanisole in cork by GC-MS

采用固相微萃取(SPME)结合气相色谱-质谱联用(GC-MS)仪测定葡萄酒用软木塞中2,4,6-三氯苯甲醚的迁移量,对整个过程引入的不确定度进行分析评定。依据CNAS-GL006:2019《化学分析中不确定度的评估指南》和JJF 1059.1—2012《测量不确定度评定与表示》,构建了不确定度评定的数学模型,分析了不确定度来源,并对各分量加以量化和合成。评定结果表明,其不确定度主要来源于标准溶液系列配制过程,其次是内标物质添加过程;当木塞中2,4,6-三氯苯甲醚迁移量为2.04 ng/L时,其扩展不确定度为0.26 ng/L(k=2)。

Uncertainty analysis was performed for the determination of releasable 2,4,6-trichloroanisole in cork used for wine by solid phase microextraction(SPME)and GC-MS.Based on CNAS-GL006:2019 Guidelines for the evaluation of uncertainty in chemical analysis and JJF 1059.1—2012 Evaluation and representation of measurement uncertainty,the mathematical model of uncertainty evaluation was constructed,the sources of uncertainty were analyzed,and the components were quantified and synthesized.The evaluation results showed that the uncertainty mainly came from the preparation process of standard solution series,followed by the additive process of internal standard substance.Furthermore,when the migration amount of 2,4,6-trichloroanisole in the cork was 2.04 ng/L,its extended uncertainty was 0.26 ng/L(k=2).