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11:09
Online Size-exclusion and Ion-exchange Chromatography on a SAXS Beamline
Published on: January 5, 2017
Optimization of step gradient separations: Consideration of nonlinear adsorption
S R Gallant1, A Kundu, S M Cramer
1Isermann Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180.
Biotechnology and Bioengineering
|August 5, 1995
Summary
Nonlinear adsorption in ion-exchange chromatography was modeled using the steric mass action isotherm. This approach accurately predicted protein separations and optimized gradient programs for preparative chromatography.
Area of Science:
- Biochemistry
- Chemical Engineering
- Chromatography
Background:
- Nonlinear adsorption significantly impacts protein behavior in preparative ion-exchange chromatography.
- Accurate modeling is crucial for optimizing separation processes.
Purpose of the Study:
- To model nonlinear cation-exchange chromatography using the steric mass action (SMA) isotherm.
- To develop a systematic method for optimizing step gradient programs.
- To investigate the influence of various factors on optimal separation conditions.
Main Methods:
- Utilized the steric mass action (SMA) isotherm in conjunction with a mass transport model.
- Performed simulations and experimental validation for step gradient separations.
- Systematically analyzed the effects of feed stream properties, concentration, and protein solubility.
Main Results:
- Demonstrated excellent agreement between simulated and experimental results for protein separations (alpha-chymotrypsinogen A, cytochrome C, lysozyme).
- Presented an effective method for selecting optimal step gradient programs.
- Evaluated the impact of high mass loading on chromatographic separations.
Conclusions:
- The SMA isotherm provides a robust model for nonlinear cation-exchange chromatography.
- The developed method enables optimization of step gradient chromatography for complex protein mixtures.
- Understanding adsorption properties is key to achieving efficient preparative protein separations.
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