Department of Analytical Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Bratislava, Slovakia.
J Sep Sci. 2011 Jul;34(13):1561-7. doi: 10.1002/jssc.201100201. Epub 2011 May 19.
Analytical potentialities of a chip-based CE in determination of ammonium in wastewaters were investigated. CZE with the electric field and/or ITP sample stacking was performed on a column-coupling (CC) chip with integrated conductivity detectors. Acetate background electrolytes (pH ∼3) including 18-crown-6-ether (18-crown-6) and tartaric acid were developed to reach rapid (in 7-8 min) CZE and ITP-CZE resolutions of ammonium from other cations (sodium, potassium, calcium and magnesium) present in wastewater samples. Under preferred working conditions (suppressed hydrodynamic flow (HDF) and EOF on the column-coupling chip), both the employed methods did provide very good repeatabilities of the migration (RSD of 0.2-0.8% for the migration time) and quantitative (RSD of 0.3-4.9% for the peak area) parameters in the model and wastewater samples. Using a 900-nL sample injection volume, LOD for ammonium were obtained at 20 and 40 μg/L concentrations in CZE and ITP-CZE separations, respectively. Very good agreements of the CZE and ITP-CZE determinations of ammonium in six untreated wastewater samples (only filtration and dilution) with the results obtained by a reference spectrometric method indicate a very good accuracy of both the CE methods presented.
研究了基于芯片的 CE 在测定废水中氨方面的分析潜力。在带有集成电导检测器的柱耦合（CC）芯片上进行了 CZE 和电场或 ITP 样品堆积。开发了包含 18-冠-6-醚（18-冠-6）和酒石酸的乙酸盐背景电解质（pH∼3），以实现快速（7-8 分钟内）CZE 和 ITP-CZE 分离废水中铵与其他阳离子（钠、钾、钙和镁）。在优选的工作条件下（在柱耦合芯片上抑制流体动力学流动（HDF）和EOF），两种方法都为迁移（迁移时间的 RSD 为 0.2-0.8%）和定量（峰面积的 RSD 为 0.3-4.9%）提供了非常好的重复性参数在模型和废水样品中。使用 900-nL 进样体积，在 CZE 和 ITP-CZE 分离中，分别在 20 和 40 μg/L 浓度下获得了对铵的检测限。用参考光谱法测定未经处理的六份废水样品（仅过滤和稀释）中的铵，CZE 和 ITP-CZE 测定结果非常吻合，表明所提出的两种 CE 方法具有非常好的准确性。
