Pelcová Pavlína, Dočekalová Hana, Kleckerová Andrea
Department of Chemistry and Biochemistry, Mendel University in Brno, Czech Republic.
Anal Chim Acta. 2015 Mar 25;866:21-26. doi: 10.1016/j.aca.2015.01.043. Epub 2015 Jan 30.
A diffusive gradient in thin films technique (DGT) was combined with liquid chromatography (LC) and cold vapor atomic fluorescence spectrometry (CV-AFS) for the simultaneous quantification of four mercury species (Hg(2+), CH3Hg(+), C2H5Hg(+), and C6H5Hg(+)). After diffusion through an agarose diffusive layer, the mercury species were accumulated in resin gels containing thiol-functionalized ion-exchange resins (Duolite GT73, and Ambersep GT74). A microwave-assisted extraction (MAE) in the presence of 6M HCl and 5 M HCl (55 °C, 15 min) was used for isolation of mercury species from Ambersep and Duolite resin gels, respectively. The extraction efficiency was higher than 95.0% (RSD 3.5%). The mercury species were separated with a mobile phase containing 6.2% methanol+0.05% 2-mercaptoethanol+0.02 M ammonium acetate with a stepwise increase of methanol content up to 80% in the 16th min on a Zorbax C18 reverse phase column. The LODs of DGT-MAE-LC-CV-AFS method were 38 ng L(-1) for CH3Hg(+), 13 ng L(-1) for Hg(2+), 34 ng L(-1) for C2H5Hg(+) and 30 ng L(-1) for C6H5Hg(+) for 24 h DGT accumulation at 25 °C.
将薄膜扩散梯度技术（DGT）与液相色谱（LC）和冷蒸气原子荧光光谱法（CV-AFS）相结合，用于同时定量四种汞形态（Hg(2+)、CH3Hg(+)、C2H5Hg(+)和C6H5Hg(+)）。汞形态通过琼脂糖扩散层扩散后，在含有硫醇官能化离子交换树脂（Duolite GT73和Ambersep GT74）的树脂凝胶中积累。分别采用在6M HCl和5M HCl存在下的微波辅助萃取（MAE）（55℃，15分钟）从Ambersep和Duolite树脂凝胶中分离汞形态。萃取效率高于95.0%（相对标准偏差3.5%）。在Zorbax C18反相柱上，使用含有6.2%甲醇+0.05% 2-巯基乙醇+0.02M醋酸铵的流动相分离汞形态，在第16分钟时甲醇含量逐步增加至80%。在25℃下进行24小时DGT积累时，DGT-MAE-LC-CV-AFS方法对CH3Hg(+)的检测限为38 ng L(-1)，对Hg(2+)为13 ng L(-1)，对C2H5Hg(+)为34 ng L(-1)，对C6H5Hg(+)为30 ng L(-1)。
