Park H M, Kim T W
Department of Chemical and Biomolecular Engineering, Sogang University, Shinsoo-Dong, Mapo-Gu, Seoul, South Korea.
Anal Chim Acta. 2007 Jun 19;593(2):171-7. doi: 10.1016/j.aca.2007.04.054. Epub 2007 May 1.
Electroosmotic flows through hydrophobic microchannels experience velocity slip at the channel wall, which increases the volumetric flow rate at a given electric potential gradient. The conventional method of zeta potential estimation using the volumetric flow rate may yield quite inaccurate zeta potential unless the velocity slip is appropriately taken care of. In the present investigation we develop a method for simultaneous estimation of zeta potential and velocity slip coefficient in the electroosmotic flow through a hydrophobic microchannel using velocity measurements. The relevant inverse problem is solved through the minimization of a performance function utilizing a conjugate gradient method. The present method is found to estimate the zeta potential and slip coefficient accurately even with noisy velocity measurements.
通过疏水微通道的电渗流在通道壁处会经历速度滑移，这会在给定电势梯度下提高体积流率。使用体积流率来估计zeta电位的传统方法可能会产生相当不准确的zeta电位，除非能适当地考虑速度滑移。在本研究中，我们开发了一种方法，通过速度测量来同时估计通过疏水微通道的电渗流中的zeta电位和速度滑移系数。利用共轭梯度法，通过最小化性能函数来解决相关的反问题。结果发现，即使存在有噪声的速度测量数据，本方法也能准确地估计zeta电位和滑移系数。
