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Phase Separation Multi-phase Flow Using an Aqueous Two-phase System of a Polyethylene Glycol/Dextran Mixed Solution.
Naoya Imanishi1, Tetsuo Yamasaki1, Kazuhiko Tsukagoshi1,2
1Department of Chemical Engineering and Materials Science, Faculty of Science and Engineering, Doshisha University.
Summary
Aqueous two-phase systems of polyethylene glycol and dextran create distinct inner and outer flows within capillary tubes. Proteins preferentially distribute into the dextran-rich inner phase, demonstrating effective phase separation for biomolecule concentration.
Area of Science:
- Fluid dynamics
- Bioseparation science
- Materials science
Background:
- Aqueous two-phase systems (ATPS) are utilized for biomolecule separation.
- Controlling multiphase flow in microchannels is crucial for advanced separation techniques.
Purpose of the Study:
- To investigate phase transformation and multiphase flow behavior of polyethylene glycol/dextran ATPS in capillary tubes.
- To analyze the distribution of proteins within the separated phases.
Main Methods:
- Fed polyethylene glycol/dextran solutions into fused-silica capillary tubes under controlled conditions.
- Observed flow patterns using bright-field microscopy.
- Analyzed protein distribution using double capillary tubes with varying inner diameters.
Main Results:
- Tube radial distribution flow (annual flow) was observed, forming dextran-rich inner and polyethylene glycol-rich outer phases.
- Proteins (bovine serum albumin, hemoglobin, lysozyme) showed higher concentration in the inner, dextran-rich phase.
- Observed protein distribution ratios (inner/outer) of 2.3, 4.2, and 1.8 for the tested proteins.
Conclusions:
- Polyethylene glycol/dextran ATPS can form stable, separated phases within capillary tubes.
- The observed tube radial distribution flow effectively concentrates proteins in the dextran-rich phase.
- This flow behavior offers a potential method for protein pre-concentration and separation in microfluidic devices.
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