SPE-HPLC双检测器法同时测定地表水中的苯并[a]芘和阿特拉津含量及不确定度评定

Simultaneous determination of Benzo[a]pyrene and Atrazine in surface water by SPE-HPLC dual detector and evaluation of uncertainty

采用全自动固相萃取(SPE)-高效液相色谱(HPLC)双检测器法同时定量分析地表水中的苯并[a]芘(BaP)和阿特拉津(AT)含量,建立了BaP和AT含量不确定度的分析方法。从样品前处理过程、样品重复测定、标准溶液配制和标准曲线拟合等方面评定了不确定度分量的贡献。评定结果显示:在影响检测结果的4个分量中,HPLC测定地表水中BaP含量时,标准曲线拟合和样品前处理过程引入的不确定度对结果影响较大,当BaP质量浓度为2.01 ng/L时,其扩展不确定度(U)为0.24 ng/L(k=2);测定AT含量时,标准溶液配制和样品重复测定引入的不确定度对结果影响较大,当AT质量浓度为50.09 ng/L时,U=4.72 ng/L(k=2)。

A method for the determination of Benzo[a]pyrene and Atrazine in surface water by automatic solid phase extraction and high-performance liquid chromatography with double detector was developed.The contribution of uncertainty component was evaluated from four aspects:sample pretreatment process,sample repeatability determination,standard solution preparation and standard curve fitting.Among the four uncertainty components,the uncertainty introduced by standard curve fitting and sample pretreatment process has a great influence on the determination of Benzo[a]pyrene content.When the content of Benzo[a]pyrene in surface water was 2.01 ng/L,the extended uncertainty was 0.24 ng/L(k=2).In the determination of Atrazine content,the uncertainty introduced by standard solution preparation and sample repeatability determination has great influence on the results.When Atrazine content was 50.09 ng/L,the extended uncertainty was 4.72 ng/L(k=2).