Quantitative assessment of flow and electric fields for electrophoretic focusing at a converging channel entrance with interfacial electrode

Michael W. Keebaugh, Prasun Mahanti, Mark Hayes

Research output: Contribution to journalArticle

4 Scopus citations


The electric field and flow field gradients near an electrified converging channel are amenable to separating and focusing specific classes of electrokinetic material, but the detailed local electric field and flow dynamics in this region have not been thoroughly investigated. Finite elemental analysis was used to develop a model of a buffer reservoir connected to a smaller channel to simulate the electrophoretic and flow velocities (which correspond directly to the respective electric and flow fields) at a converging entrance. A detailed PTV (Particle Tracking Velocimetry) study using charged fluorescent microspheres was performed to assess the model validity both in the absence and presence of an applied electric field. The predicted flow velocity gradient from the model agreed with the PTV data when no electric field was present. Once the additional forces that act on the large particles required for tracing (dielectrophoresis) were included, the model accurately described the velocity of the charged particles in electric fields.

Original languageEnglish (US)
Pages (from-to)1924-1930
Number of pages7
Issue number13
StatePublished - Jul 1 2012



  • Counterflow separations
  • Electrokinetic effects
  • Electrophoretic focusing
  • Particle tracking velocimetry

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Clinical Biochemistry

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