Column Modelling
Column modeling has been a major area of research of the Cramer group. We have worked on modeling ion exchange, displacement, immobilized metal affinity and hydrophobic interaction chromatography. The ability to effectively model chromatographic profiles can give many insights into the fundamentals and mechanisms of the chromatographic process as well as being used as a powerful predictive tool. It can also help to explore experimental conditions much faster than experimental methods without the need for large quantities of materials.
The Steric Mass-Action isotherm for ion exchange, which was developed in our group, and column simulations have been used to show the isotherm’s ability to explain chromatographic behavior of proteins.
Modeling of displacement chromatography has also been useful in understanding the formation and movement of shock layers through the chromatographic column as well as predicting the order and shape of elution profiles.
Modeling can also be used as a tool for parameter estimation and optimization. Chromatographic profiles can be used along with column simulations to fit parameters that are otherwise difficult to obtain. From these parameters the simulation can be very useful as a tool for predicting elution profiles.
Selected References:
- Brooks, Clayton A. and Cramer . “Steric Mass-Action Ion Exchange: Displacement Profiles and Induced Salt Gradients.” AIChE Journal 38 (1992): 1969-1978.
- Gallant, Stuart R. and Cramer . “Productivity and operating regimes in protein chromatography using low-molecular-mass displacers.” Journal of Chromatography A 771 (1997): 9-22.
- Gallant, Stuart R., et al. “Modeling non-linear elution of proteins in ion-exchange chromatography.” Journal of Chromatography A 702 (1995): 125-142.
- Gallant, Stuart R., et al. “Modeling Gradient Elution of Proteins in Ion-Exchange Chromatography.” AIChE Journal 42 (1996): 2511-2520.
- Gallant, S.R., et al. “Optimization of preparative ion-exchange chromatography of proteins: linear gradient separations.” Journal of Chromatography A 725 (1996): 295-314.
- Ladiwala, Asif, et al. “A priori prediction of adsorption isotherm parameters and chromatographic behavior in ion-exchange systems.” PNAS 102 (2005): 11710-11715.
- Nagrath, Deepak, et al. “Characterization and modeling of nonlinear hydrophobic interaction chromatographic systems.” Journal of Chromatography A 1218 (2011): 1219-1226.
- Natarajan, Venkatesh and Cramer . “Modeling Shock Layers in Ion-Exchange Displacement Chromatography.” AIChE Journal 45 (1999): 27-37.
- Vunnum, Suresh, et al. “Immobilized metal affinity chromatography: Modeling of nonlinear multicomponent equilibrium.” Chemical Engineering Science 50 (1995): 1785-1803.