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Microfluidic Free-Flow Isoelectric Focusing with Real-Time pI Determination

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Microfluidic Electrophoresis

Part of the book series: Methods in Molecular Biology ((MIMB,volume 1906))

Abstract

Free-flow electrophoresis (FFE) may be used for continuous and preparative separation of a wide variety of biomolecules. Isoelectric focusing (IEF) provides for the separation of compounds according to their isoelectric point (pI). Here we describe a microfluidic chip-based protocol for the fabrication, application, and optical monitoring of free-flow isoelectric focusing (FFIEF) of proteins and peptides on the microscale with optical surveillance of the microscopic pH gradient provided by an integrated pH sensing layer. This protocol may be used with modifications also for the FFIEF of other biomolecules and may serve as template for the fabrication of microfluidic chips with integrated fluorescent or luminescent pH sensor layers for FFE and other applications.

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Authors and Affiliations

  1. Department of Chemistry, The Hong Kong University of Science and Technology, Kowloon, Hong Kong SAR, China

    Stefan Nagl

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  1. Stefan Nagl
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Correspondence to Stefan Nagl .

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Editors and Affiliations

  1. Department of Chemistry, University of Wyoming, Laramie, WY, USA

    Debashis Dutta

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Nagl, S. (2019). Microfluidic Free-Flow Isoelectric Focusing with Real-Time pI Determination. In: Dutta, D. (eds) Microfluidic Electrophoresis. Methods in Molecular Biology, vol 1906. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-8964-5_8

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  • DOI: https://doi.org/10.1007/978-1-4939-8964-5_8

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  • Publisher Name: Humana Press, New York, NY

  • Print ISBN: 978-1-4939-8963-8

  • Online ISBN: 978-1-4939-8964-5

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