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Cell Co-culture Patterning Using Aqueous Two-phase Systems
Published on: March 26, 2013
"On the Collander equation": protein partitioning in polymer/polymer aqueous two-phase systems
Pedro P Madeira1, José A Teixeira, Eugénia A Macedo
1Laboratory of Separation and Reaction Engineering, Dpt. de Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, s/n 4200-465, Porto, Portugal.
Journal of Chromatography. A
|April 2, 2008
Summary
This study measured protein distribution in aqueous two-phase systems (ATPSs) using various polymers like Dextran and polyethylene glycol. Protein distribution coefficients were correlated using a regression equation, aiding in predicting protein partitioning behavior.
Area of Science:
- Biochemistry
- Separation Science
- Polymer Chemistry
Background:
- Aqueous two-phase systems (ATPSs) are widely used for protein separation and purification.
- Understanding protein partitioning behavior in different ATPSs is crucial for optimizing separation processes.
Purpose of the Study:
- To measure protein distribution coefficients in various ATPSs.
- To correlate protein partitioning behavior using a regression equation.
- To evaluate the effectiveness of different polymer combinations for protein separation.
Main Methods:
- Proteins were partitioned in ATPSs formed by Dextran-75, Ficoll-70, polyethylene glycol-8000, hydroxypropyl starch-100, and Ucon50HB5100.
- All systems contained 0.15M NaCl in 0.01 M phosphate buffer, pH 7.4.
- Distribution coefficients were measured and correlated using the solvent regression equation: lnKi=aiolnKo+bio.
Main Results:
- Most proteins precipitated at the interface in the polyethylene glycol-Ucon system.
- Protein distribution coefficients in other ATPSs (PES-PEG, PES-Ucon, Ficoll-PEG, Ficoll-Ucon, Dex-PEG, Dex-Ucon) were successfully correlated.
- The constants aio and bio in the regression equation depend on the specific ATPS composition.
Conclusions:
- The study provides a predictive model for protein partitioning in various ATPSs.
- The findings aid in selecting appropriate ATPSs for specific protein separation challenges.
- The regression equation offers a valuable tool for optimizing bioseparation processes.
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