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  • Revisit of wall-induced lateral migration in particle electrophoresis through a straight rectangular microchannel: effects of particle zeta potential
Title: Revisit of wall-induced lateral migration in particle electrophoresis through a straight rectangular microchannel: effects of particle zeta potential
Previous studies have reported a lateral migration in particle electrophoresis through a straight rectangular microchannel. This phenomenon arises from the inherent wall-induced electrical lift that can be exploited to focus and separate particles for microfluidic applications. Such a dielectrophoretic-like force has been recently found to vary with the buffer concentration. We demonstrate in this work that the particle zeta potential also has a significant effect on the wall-induced electrical lift. We perform an experimental study of the lateral migration of equal-sized polystyrene particles with varying surface charges under identical electrokinetic flow conditions. Surprisingly, an enhanced focusing is observed for particles with a faster electrokinetic motion, which indicates a substantially larger electrical lift for particles with a smaller zeta potential. We speculate this phenomenon may be correlated with the particle surface conduction that is a strong function of particle and fluid properties.  more » « less
Award ID(s):
1704379
PAR ID:
10064136
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
ELECTROPHORESIS
ISSN:
0173-0835
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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