Electromigration diffusivity spectrometry: A way for simultaneous determination of diffusion coefficients from mixed samples
Electromigration diffusivity spectrometry: A way for simultaneous determination of diffusion coefficients from mixed samples
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DOI：
10.1002/elps.201000252
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发表时间：
2010-09
期刊：
影响因子：
2.9
通讯作者：
Suhua Yang;Yiming Zhang;Tao Liao;Zhenpeng Guo;Yi Chen
中科院分区：
文献类型：
--
作者：
Suhua Yang;Yiming Zhang;Tao Liao;Zhenpeng Guo;Yi Chen
提出了一种新的方法，用于同时测量扩散系数，（D），从混合样品的电泳和所谓的电迁移扩散光谱。经过理论处理，导出了实用的D-方程。通过实验室建立的改进CE系统，实现了基于电迁移的扩散系数光谱法，并验证了其适用于混合芳香族氨基酸、酚类和芳香族有机酸扩散系数的快速准确测定，通过峰面积与D的关系给出扩散系数谱，与质谱非常相似。测定的精密度主要取决于运行缓冲液的pH值，其选择应使分析物和内标物在0.5e以上带电。必须在远离彼此和分析物的电通量下选择标准物。在这些情况下，发现样品和运行缓冲液浓度、电压和系统温度对测定的影响可忽略不计。在我们的试验中，所获得的测量精度一般保持在1%以内的五个运行，和D的测量值与文献中的值吻合良好，偏差小于2.2%，正确使用校准标准。
A novel method was proposed for simultaneous measurement of diffusion coefficients, (D), from mixed samples by electrophoresis and termed electromigration‐based diffusivity spectrometry. After theoretical treatment, D‐equation for practical use has been deduced. With a modified CE system built in laboratory, electromigration‐based diffusivity spectrometry has been realized and validated to suit for fast and accurate determination of diffusivities of mixed aromatic amino acids, phenols and aromatic organic acid, giving diffusivity spectra by peak area versus D, much similar to mass spectra. The precision of the measurement was found to critically depend on pH value of running buffer, which should be so selected that the analytes and internal standards could be charged at above 0.5e. The standards have to be selected at an electric flux far from each other and from analytes. In these cases, sample and running buffer concentrations, voltage and system temperature were found to have only negligible impact on the determination. In our test, the obtained measuring precision was generally kept within 1% for five runs, and the measured values of D agreed well with those from literature, with a deviation of less than 2.2% after the right use of calibration standards.