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Separating Beads and Cells in Multi-channel Microfluidic Devices Using Dielectrophoresis and Laminar Flow
Published on: February 4, 2011
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Application of an electrokinetic backflow for enhancing pressure-driven charge based separations in sub-micrometer
Ling Xia1, Rajesh Deb1, Naoki Yanagisawa1
1Department of Chemistry, University of Wyoming, Laramie, WY, 82071, USA.
Analytica Chimica Acta
|October 25, 2022
Summary
Introducing an electrokinetic backflow significantly enhances pressure-driven separations in microchannels. This method improves separation resolution by over tenfold for amino acid analysis.
Area of Science:
- Analytical Chemistry
- Microfluidics
- Separation Science
Background:
- Pressure-driven separations in microchannels face limitations in resolving power.
- Electrokinetic phenomena can influence fluid dynamics and separation efficiency.
Purpose of the Study:
- To improve the resolving power of pressure-driven charge-based separations in sub-micrometer channels.
- To investigate the effect of electrokinetic backflow on separation performance.
Main Methods:
- Implementing an electrokinetic backflow in sub-micrometer deep glass channels.
- Generating pressure-driven flow using an on-chip polyacrylamide gel membrane.
- Optimizing electrical voltage to control electrokinetic backflow.
Main Results:
- Achieved significant improvements in separation resolution, exceeding an order of magnitude.
- Demonstrated that axial electrophoresis aids pressure-driven separation in negatively charged channels.
- Observed prolonged sample exposure to the electric field and increased fluid shear due to electroosmotic backflow.
Conclusions:
- Electrokinetic backflow is a powerful strategy to enhance resolution in microchannel separations.
- The developed method offers a substantial improvement over conventional pressure-driven techniques.
- Further assessment of band broadening confirmed its dependence on operating conditions.
Keywords:
Band broadeningCharge based separationElectrokinetic backflowMicropumpPressure-driven flowSub-micrometer deep channelMore Related Videos
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