Measuring Electroosmotic Flow in Microchips and Capillaries

  • S. Douglass Gilman
  • Peter J. Chapman
Part of the Methods in Molecular Biology book series (MIMB, volume 339)

Abstract

Electrophoretic migration and electroosmotic flow (EOF) combine to determine the migration rate of charged compounds in capillary electrophoresis (CE) and microchip capillary electrophoresis (MCE). Uncontrolled and unmeasured changes in EOF will lead to irreproducible peak migration times and poor peak quantitation. The two most common methods for measuring EOF for CE and MCE are detailed. Experimental results for application of the neutral marker method and the current monitoring method to EC are presented, and related calculations of EOF rates and electroosmotic mobility are described. The strengths and shortcomings of these two EOF measurement techniques are discussed. Additional approaches for studying and measuring EOF and for improving the reproducibility of migration times for CE and MCE are summarized.

Key Words

Electroosmotic flow microchip capillary electrophoresis capillary electrophoresis neutral marker current monitoring 

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Copyright information

© Humana Press Inc. 2006

Authors and Affiliations

  • S. Douglass Gilman
    • 1
  • Peter J. Chapman
    • 2
  1. 1.Department of ChemistryLouisiana State UniversityBaton Rouge
  2. 2.Department of ChemistryUniversity of TennesseeKnoxville

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