title: Transient electro-osmotic flow in cylindrical microcapillaries containing salt-free medium.
abstract: A theoretical study on the transient electro-osmotic flow through a cylindrical microcapillary containing a salt-free medium is presented for both constant surface charge density and constant surface potential. The exact analytical solutions for the electric potential distribution and the transient electro-osmotic flow velocity are derived by solving the nonlinear Poisson-Boltzmann equation and the Navier-Stokes equation. Based on these results, a systematic parametric study on the characteristics of the transient electro-osmotic flow is detailed. The general behavior of transient electro-osmotic flow in a cylindrical tube is similar to that observed in a microchannel containing an electrolyte solution. However, the steady-state electro-osmotic flow significantly deviates from the typical plug flow at higher surface charge and the rate of increase in the electro-osmotic mobility is strongly suppressed due to the effect of counterion condensation. In addition, the applicability limit of these solutions is also discussed.
authors.affiliation: Department of Mechanical Engineering, Far East University, Tainan 744, Taiwan.
authors.forename: Shih-Hsiang
authors.initials: SH
authors.lastname: Chang
references.citation: J Colloid Interface Sci. 2002 Nov 1;255(1):202-7
references.pmid: 12702386
references.citation: J Colloid Interface Sci. 1997 Nov 15;195(2):388-94
references.pmid: 9441640
references.citation: Anal Chem. 1995 Sep 1;67(17):2743-9
references.pmid: 8779410
references.citation: J Colloid Interface Sci. 2003 Jun 1;262(1):294-7
references.pmid: 16256607
references.citation: J Phys Chem B. 2006 Jan 26;110(3):1490-8
references.pmid: 16471701
references.citation: J Colloid Interface Sci. 2002 Apr 15;248(2):499-503
references.pmid: 16290556
references.citation: Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Feb;75(2 Pt 1):021502
references.pmid: 17358343
references.citation: Anal Chem. 1999 Jun 1;71(11):2199-204
references.pmid: 21662757
references.citation: J Colloid Interface Sci. 2004 Jan 1;269(1):255-8
references.pmid: 14651919
references.citation: Colloids Surf B Biointerfaces. 2004 Nov 15;38(3-4):139-41
references.pmid: 15542315
references.citation: J Colloid Interface Sci. 2002 Apr 15;248(2):524-7
references.pmid: 16290559
references.citation: J Colloid Interface Sci. 2003 Sep 15;265(2):422-7
references.pmid: 12962677
references.citation: Anal Chem. 1998 May 1;70(9):1870-81
references.pmid: 21651279
references.citation: Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Aug;70(2 Pt 1):021506
references.pmid: 15447495