Artículo
Wall Repulsion of Charged Colloidal Particles during Electrophoresis in Microfluidic Channels
Autor/es | Fernández Mateo, Raúl
Calero, Víctor Morgan, Hywel García Sánchez, Pablo Ramos Reyes, Antonio |
Departamento | Universidad de Sevilla. Departamento de Electrónica y Electromagnetismo |
Fecha de publicación | 2022 |
Fecha de depósito | 2023-01-19 |
Publicado en |
|
Premios | Premio Anual Publicación Científica Destacada de la US. Facultad de Física |
Resumen | Electrophoresis describes the motion of charged particles suspended in electrolytes when subjected to an external electric field. Previous experiments have shown that particles undergoing electrophoresis are repelled from ... Electrophoresis describes the motion of charged particles suspended in electrolytes when subjected to an external electric field. Previous experiments have shown that particles undergoing electrophoresis are repelled from nearby channel walls, contrary to the standard description of electrophoresis that predicts no hydrodynamic repulsion. Dielectrophoretic (DEP) repulsive forces have been commonly invoked as the cause of this wall repulsion. We show that DEP forces can only account for this wall repulsion at high frequencies of applied electric field. In the presence of a low-frequency field, quadrupolar electro-osmotic flows are observed around the particles. We experimentally demonstrate that these hydrodynamic flows are the cause of the widely observed particle-wall interaction. This hydrodynamic wall repulsion should be considered in the design and application of electric-field-driven manipulation of particles in microfluidic devices. |
Agencias financiadoras | Ministerio de Ciencia e Innovación (MICIN). España |
Identificador del proyecto | PGC2018-099217-B-I00
10.13039/501100011033 |
Cita | Fernández Mateo, R., Calero, V., Morgan, H., García Sánchez, P. y Ramos Reyes, A. (2022). Wall Repulsion of Charged Colloidal Particles during Electrophoresis in Microfluidic Channels. Physical Review Letters, 128 (7), 074501. https://doi.org/10.1103/PhysRevLett.128.074501. |
Ficheros | Tamaño | Formato | Ver | Descripción |
---|---|---|---|---|
Wall Repulsion of Charged.pdf | 770.8Kb | [PDF] | Ver/ | |