Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 10617.
Langmuir. 2010 Nov 16;26(22):16857-64. doi: 10.1021/la102968u. Epub 2010 Oct 5.
It is often assumed in the conventional electrophoresis analysis that the liquid phase contains only one kind of each cation and anion. That analysis is extended to the case where the liquid phase contains multiple ionic species in this study so that the conditions considered are closer to reality. Using a dispersion of SiO(2) particles, which is of a charge-regulated nature, as an example, where the dispersion pH is adjusted by HCl and NaOH, numerical simulation is conducted to examine the electrophoretic behaviors of the particle under various conditions. We show that the presence of multiple ionic species is capable of yielding profound and interesting electrophoretic behaviors, which are justified by the experimental data in the literature. In addition, we show that two types of double-layer polarization (DLP) are present that have not been reported previously in the electrophoresis analyses. Type I DLP, which reduces the mobility of a particle, occurs inside the double layer, and type II DLP, which raises that mobility, occurs immediately outside the double layer.
在常规电泳分析中，通常假设液相中只含有一种阳离子和阴离子。本研究将该分析扩展到液相中存在多种离子物种的情况，以便更接近实际情况。以具有电荷调节性质的 SiO2 颗粒分散体为例，通过 HCl 和 NaOH 调节分散体 pH，进行数值模拟以检查在各种条件下颗粒的电泳行为。结果表明，多种离子物种的存在能够产生深刻而有趣的电泳行为，这些行为得到了文献中实验数据的证实。此外，我们还表明，存在两种以前在电泳分析中未报道过的双层极化（DLP）类型。降低颗粒迁移率的 I 型 DLP 发生在双电层内部，而提高迁移率的 II 型 DLP 发生在双电层外部。
