Estimating Stream Broadening in Free-Flow Electrophoretic Systems Based on the Method-of-Moments Formulation

  • Debashis DuttaEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1906)


The resolving power of free-flow electrophoretic assays is often limited by the broadening of analyte streams as they migrate through the separation chamber. While molecular diffusion and flow hydrodynamics inherently contribute to such dispersion, non-idealities such as Joule heating and unwanted pressure-driven cross-flows among others can also significantly modify these contributions. In this chapter, we describe a theoretical approach to estimating stream broadening in free-flow electrophoretic systems under steady-state conditions based on the method-of-moments formulation. This methodology allows the determination of the spatial moments of solute concentration, thereby yielding measures for the mean position and spatial variance of the analyte stream.

Key words

Electrodynamic dispersion Free-flow electrophoresis Free-flow isoelectric focusing Hydrodynamic dispersion Method-of-moments 


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of ChemistryUniversity of WyomingLaramieUSA

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