Department of Chemical and Biomolecular Engineering, Sogang University, Seoul, South Korea.
Electrophoresis. 2013 Mar;34(5):651-61. doi: 10.1002/elps.201200484. Epub 2013 Feb 6.
In the present investigation, it is found that the electrophoretic mobility of hydrophobic particles is affected not only by the zeta potential but also by the velocity slip at the particle surface. From a physicochemical viewpoint, zeta potential represents the surface charge properties and the slip coefficient indicates the hydrophobicity of the particle surface. Thus, it is necessary to separate the contribution of zeta potential from that of slip coefficient to the particle mobility, since zeta potential can be changed by varying the bulk ionic concentration while the slip coefficient can be modified by adjusting surfactant concentration. In the present investigation, a method is devised that allows a simultaneous estimation of zeta potential and slip coefficient of micro and nanoparticles using measurements of electrophoretic mobility at various bulk ionic concentrations. Employing a nonlinear curve-fitting technique and an analytic solution of electrophoresis for a particle with velocity slip, the present technique predicts both zeta potential and slip coefficient simultaneously with reasonable accuracy using the measured values of electrophoretic mobility at various bulk ionic concentrations.
在本研究中发现，疏水性颗粒的电泳迁移率不仅受到 zeta 电位的影响，还受到颗粒表面速度滑移的影响。从物理化学的角度来看，zeta 电位代表表面电荷特性，滑移系数表示颗粒表面的疏水性。因此，有必要将 zeta 电位和滑移系数对颗粒迁移率的贡献分开，因为 zeta 电位可以通过改变体相离子浓度来改变，而滑移系数可以通过调整表面活性剂浓度来改变。在本研究中，设计了一种方法，可以使用在各种体相离子浓度下测量的电泳迁移率来同时估计微纳米颗粒的 zeta 电位和滑移系数。本技术使用非线性曲线拟合技术和具有速度滑移的颗粒的电泳分析解，使用在各种体相离子浓度下测量的电泳迁移率值，可以合理准确地同时预测 zeta 电位和滑移系数。
