Related Experiment Video
Updated: Aug 8, 2026

Online Size-exclusion and Ion-exchange Chromatography on a SAXS Beamline
Published on: January 5, 2017
Comparison of linear gradient and displacement separations in ion-exchange systems
V Natarajan1, S Ghose, S M Cramer
1Department of Chemical Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
Abstract:
The linear gradient mode of chromatography is the most widely employed mode of operation in ion-exchange chromatographic separations. However, in recent years, the displacement mode has received considerable attention because of its promise of high throughput and high resolution. To enable a comparison of these two modes of chromatography, it is essential to identify the optimum operating conditions for each. We employed an iterative algorithm to carry out the necessary optimization. The Steric Mass Action model of ion-exchange chromatography is used in concert with the solid-film linear-driving force model to describe the chromatographic behavior of the solutes in these systems. The performances of displacement and gradient modes of chromatography are compared for different types of separation problems. It turns out that for "easy" separations, both the modes are equally effective. However, for challenging separations, the displacement mode is superior to the gradient mode. Our results shed significant light on the performance of gradient and displacement modes in protein ion-exchange systems.
More Related Videos
08:06Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
10:41Ion Exchange Chromatography (IEX) Coupled to Multi-angle Light Scattering (MALS) for Protein Separation and Characterization
Published on: April 5, 2019
Related Concept Videos
Ion Exchange
Analyte Adsorption and Distribution
Chromatographic Resolution
The effectiveness of separation can be evaluated by determining the level of separation between two neighboring peaks in a chromatogram, which represents the individual components of a sample.
In chromatography,...
Optimizing Chromatographic Separations
Band broadening refers to spreading solute bands as they travel through the column. This broadening can impact resolution. Plate height (H) represents the length required for one theoretical plate. A lower plate height corresponds to...
High-Performance Liquid Chromatography: Elution Process
Ion-Exchange Chromatography