Zhang Yanlin, Miró Manuel, Kolev Spas D
Centre for Aquatic Pollution Identification and Management (CAPIM), School of Chemistry, The University of Melbourne, Victoria 3010, Australia.
FI-TRACE group, Department of Chemistry, Faculty of Science, University of the Balearic Islands, Carretera de Valldemossa km 7.5, E-07122 Palma de Mallorca, Spain.
Talanta. 2018 Feb 1;178:622-628. doi: 10.1016/j.talanta.2017.09.084. Epub 2017 Sep 30.
A method for the automatic simultaneous assessment of mobility and lability of mercury in environmental solid samples has been developed for the first time. It has been implemented in a hybrid flow system integrating flow-through dynamic sequential extraction and on-line chemical digestion prior to atomic fluorescence detection. The method allows the determination of trace concentrations of labile mercury (Hg) and non-labile mercury (Hg) in different bioaccessible phases of environmental solid samples thus providing expeditious data not only for Hg exposome studies but also for the selection of suitable environmental remediation techniques. The analytical procedure involves the sequential application of deionized water, 0.01M HNO solution, 1M KOH solution and solution containing both NaS and KOH (1molL each) to a solid sample packed in a column to release four Hg fractions according to their mobilities (i.e. water soluble, exchangeable, organic matter associated, and sulfide bound Hg) followed by the on-line determination of the concentrations of Hg and Hg by flow programming. Apart from obtaining more comprehensive knowledge of risk exposure of Hg-laden solids, important advantages of the newly developed method compared to its batch-wise fractionation counterpart include (i) approximately 8-fold reduction in the time for acquisition of the dynamic extraction data, (ii) evaluation of the kinetics of release of Hg, (iii) Hg lability analysis, and (iv) minimization of matrix interferences and potential re-adsorption or transformation of the extracted Hg species.
首次开发了一种用于自动同时评估环境固体样品中汞的迁移率和活性的方法。该方法已在一个混合流动系统中实施，该系统集成了流通式动态顺序萃取和原子荧光检测前的在线化学消解。该方法能够测定环境固体样品不同生物可利用相中痕量的活性汞（Hg）和非活性汞（Hg），从而不仅为汞暴露组研究，也为选择合适的环境修复技术提供快速数据。分析程序包括依次将去离子水、0.01M HNO溶液、1M KOH溶液以及含有NaS和KOH（各1mol/L）的溶液应用于填充在柱中的固体样品，以根据汞的迁移率（即水溶性、可交换性、与有机物结合以及与硫化物结合的汞）释放四个汞组分，随后通过流动程序在线测定Hg和Hg的浓度。除了获得关于含汞固体风险暴露的更全面知识外，与分批分级法相比，新开发方法的重要优势包括：（i）获取动态萃取数据的时间减少约8倍；（ii）评估汞的释放动力学；（iii）汞活性分析；（iv）最大限度减少基质干扰以及萃取的汞物种的潜在再吸附或转化。
