Issue 29, 2016

Experimental and theoretical investigations of non-Newtonian electro-osmotic driven flow in rectangular microchannels

Abstract

With the development of microfluidics, electro-osmotic (EO) driven flow has gained intense research interest as a result of its unique flow profile and the corresponding benefits in its application in the transportation of sensitive samples. Sensitive samples, such as DNA, are incapable of enduring strong flow shear induced by conventional hydrodynamic driven methods. EO driven flow is thus a niche area. However, even though there are a few research studies focusing on bio-fluidic samples related to EO driven flow, the majority of them are merely theoretical modeling without solid evidence from experiments due to the inherent complex rheological behavior of the bio-fluids. Challenges occur when the EO driven mechanism meets with complex rheology; vital questions such as can the zeta potential still be assumed to be constant when dealing with fluids with complex rheology? and “Does the shear thinning effect enhance electro-osmotic driven flow?” need to be answered. We conducted experiments using current monitoring and microscopy fluorescence methods, and developed a theoretical model by coupling a generalized Smoluchowski approach with the power-law constitutive model. We calculated the zeta potential and compared the experimental results with modeling to answer the questions. The results show a reduction of zeta potential in the presence of PEO aqueous solutions. A constant zeta potential is also indicated by varying the PEO concentration and the electric field strength.The shear thinning effect is also addressed via experimental data and theoretical calculations. The results show a promising enhancement of the EO driven velocity due to the shear thinning effect.

Graphical abstract: Experimental and theoretical investigations of non-Newtonian electro-osmotic driven flow in rectangular microchannels

Article information

Article type
Paper
Submitted
17 Feb 2016
Accepted
10 Jun 2016
First published
22 Jun 2016

Soft Matter, 2016,12, 6206-6213

Experimental and theoretical investigations of non-Newtonian electro-osmotic driven flow in rectangular microchannels

Y. Huang, J. Chen, T. Wong and J. Liow, Soft Matter, 2016, 12, 6206 DOI: 10.1039/C6SM00408C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements