Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Chongqing University, Chongqing 400045, China; Central Lab of Chongqing Water Conservancy Investment Group Co., Ltd, Chongqing 401331, China.
Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, State Ministry of Education, Chongqing University, Chongqing 400045, China.
Talanta. 2018 Mar 1;179:86-91. doi: 10.1016/j.talanta.2017.10.003. Epub 2017 Oct 5.
In this paper, a procedure for in-situ pre-concentration in graphite furnace by repeated sampling and pyrolysis is proposed for the determination of ultra-trace thallium in drinking water by graphite furnace atomic absorption spectrometry (GF-AAS). Without any other laborious enrichment processes that routinely result in analyte loss and contamination, thallium was directly concentrated in the graphite furnace automatically and subsequently subject to analysis. The effects of several key factors, such as the temperature for pyrolysis and atomization, the chemical modifier, and the repeated sampling times were investigated. Under the optimized conditions, a limit of detection of 0.01µgL was obtained, which fulfilled thallium determination in drinking water by GB 5749-2006 regulated by China. Successful analysis of thallium in certified water samples and drinking water samples was demonstrated, with analytical results in good agreement with the certified values and those by inductively coupled plasma mass spectrometry (ICP-MS), respectively. Routine spike-recovery tests with randomly selected drinking water samples showed satisfactory results of 80-96%. The proposed method is simple and sensitive for screening of ultra-trace thallium in drinking water samples.
本文提出了一种在石墨炉中通过重复取样和热解进行原位预浓缩的方法，用于通过石墨炉原子吸收光谱法（GF-AAS）测定饮用水中的痕量铊。无需进行常规的繁琐富集过程，这些过程通常会导致分析物损失和污染，铊可以直接在石墨炉中自动浓缩，然后进行分析。研究了几种关键因素的影响，例如热解和原子化温度、化学修饰剂和重复取样次数。在优化条件下，检测限达到 0.01µgL，满足中国国家标准 GB 5749-2006 对饮用水中铊的测定要求。成功地对认证水样和饮用水样中的铊进行了分析，分析结果分别与认证值和电感耦合等离子体质谱（ICP-MS）相符。用随机选择的饮用水样进行的常规加标回收测试显示出令人满意的 80-96%的结果。该方法简单灵敏，可用于筛选饮用水样中的痕量铊。
