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Updated: Aug 8, 2026
06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Phase partitioning in space and on earth
J M Van Alstine1, L J Karr, J M Harris
1Biophysics Branch, NASA/Marshall Space Flight Center, Huntsville, AL 35812.
Advances in Experimental Medicine and Biology
|January 1, 1987
Summary
Polymer-based aqueous two-phase systems enable differential partitioning of biological materials. This technique is being explored for low-gravity biomaterials processing, leveraging unique demixing properties in space.
Area of Science:
- Biotechnology
- Materials Science
- Biophysics
Background:
- Neutral polymers like dextran and poly(ethylene glycol) (PEG) form aqueous two-phase systems (ATPS).
- Biological particles and macromolecules partition differentially between these phases and the interface.
- Partitioning behavior relates to surface properties like membrane charge and lipid composition.
Purpose of the Study:
- Investigate the influence of gravity on ATPS separation efficiency.
- Explore the potential of ATPS for low-gravity biomaterials processing.
- Understand polymer surface coating effects on phase separation and electroosmosis.
Main Methods:
- Utilizing dextran-poly(ethylene glycol) aqueous two-phase systems.
- Studying demixing phenomena in Earth and low-gravity environments.
- Synthesizing PEG-derivatized antibodies for immunoaffinity partitioning.
- Investigating polymer surface coatings for phase localization control.
Main Results:
- Biological particles and macromolecules exhibit differential partitioning in ATPS.
- Low-gravity conditions alter demixing primarily through coalescence.
- Polymer surface coatings influence phase localization and electroosmosis.
- PEG-derivatized antibodies facilitate specific cell partitioning.
Conclusions:
- Aqueous two-phase systems offer versatile bioseparation capabilities.
- Understanding gravity's influence is crucial for space-based biomaterials processing.
- ATPS, particularly with affinity ligands, holds promise for advanced bioparticle separation in microgravity.
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