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Updated: Jul 3, 2026
06:53
Cell Fractionation of U937 Cells in the Absence of High-speed Centrifugation
Published on: January 18, 2019
Protein fractionation using electrostatic interactions in membranel filtration.
R H van Eijndhoven1, S Saksena, A L Zydney
1Department of Chemical Engineering, University of Delaware, Newark, Delaware 19716, USA.
Biotechnology and Bioengineering
|November 20, 1995
Summary
Improving membrane protein fractionation selectivity is achievable by manipulating electrostatic interactions. This study enhanced separation of albumin and hemoglobin by adjusting salt concentration and pH, demonstrating effective membrane filtration for similar molecular weight proteins.
Area of Science:
- Biochemistry
- Chemical Engineering
- Materials Science
Background:
- Membrane systems are crucial for protein fractionation.
- Poor selectivity has historically limited their effectiveness.
- Exploiting protein-membrane electrostatic interactions offers a novel approach.
Purpose of the Study:
- To significantly enhance the selectivity of membrane systems for protein fractionation.
- To investigate the impact of electrostatic interactions on separation efficiency.
- To demonstrate effective separation of proteins with similar molecular weights.
Main Methods:
- Utilized membrane filtration techniques, including batch filtration and continuous diafiltration.
- Manipulated salt concentration and pH to control electrostatic interactions.
- Analyzed separation factors and protein recovery rates.
Main Results:
- Achieved a separation factor exceeding 70 for the albumin-hemoglobin system by optimizing pH and salt concentration.
- Demonstrated high selectivity due to strong electrostatic exclusion of charged albumin.
- Obtained over 70% hemoglobin recovery and a purification factor of approximately 100 using diafiltration.
Conclusions:
- Membrane systems can achieve high selectivity for protein fractionation by leveraging electrostatic interactions.
- Optimized conditions allow for effective separation of proteins with similar molecular weights.
- This approach holds significant potential for advancing protein separation technologies.
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