Separation of Protein with Chromatography

Chromatography has become indispensable as a method for separating target substances from a suspension. Based on the experiments of our project partner Merck, we determine suitable model parameters to map the processes in the simulation.

Modelling and Simulation of Chromatography with Spherical Beads

BMBF Joint Research Project AMSCHA »Analysis, Modelling and Simulation of Chromatographic Purification Processes«

In the BMBF joint research project AMSCHA, we develop models for the simulation of separation processes of protein and cell suspensions. The abbreviation stands for »Analysis, modelling and simulation of chromatographic purification processes«. In collaboration with researchers from the Technische Universität Kaiserslautern and the University of Applied Sciences Darmstadt, the processes are investigated on different length scales. The chemical and pharmaceutical company Merck KGaA and the manufacturer of optical microscopes Leica Microsystems support the research project as industrial partners.

The separation of target substances from a suspension is an important and often undervalued step in the manufacturing of agents in the pharmaceutical industry, although one cannot imagine laboratory and industrial work without chromatography as a separation process. One well-established form is column chromatography. The efficiency and the throughput of these columns strongly depend on the process conditions and the used chromatographic media.

Model, Simulate and Optimize Protein Purification

In one part of the project, we consider the separation of protein suspensions using chromatographic purification. The goal is to extract one target protein from a mixture. This is done with the help of spherical, microporous beads (pearls). In column chromatography, a cylindrical tube – the separating column – is packed with the stationary phase – the beads – and is flowed through by a protein suspension. In this connection, part of the proteins is deposited within the beads. 

Chromatography Bead
© Merck KGaA
Microscopy image of a chromatography bead
Labeled Bead
© Merck KGaA
Confocal laser scanning microscopy image of a labeled bead. The dye intensity is indicating the loading (lightest red strongest loading).
Overview on the simulation of a chromatography column
© Fraunhofer ITWM
Overview on the simulation of a chromatography column (dynamic process conditions; left: concentration profile in the column, right: the loading of single beads at different positions in the column).

The industry partner Merck conducts for this application several experiments in the laboratory. To reproduce the processes in the simulation, we determine suitable model parameters based on static and dynamic measurements of the binding capacities (protein concentration). Additionally, Merck visualizes the concentration profiles in the static experiments using confocal laser scanning microscopy.

For this, a coupled multiscale modelling is essential to account for the effects on both, the bead scale (micro scale) and the column scale (macro scale). Required model parameters are the transport and adsorption properties of the beads as well as the specification of the protein transfer from the suspension to the bead. Based on static experiments, a prediction and optimization of the dynamic process is possible. With the assistance of these simulation techniques, it is additionally possible to visualize the loading of the beads also for the dynamic process and to illustrated possible improvements in the design of the column.

 

Project Partners

Vorverpackte  Chromatographiesäulen der Firma Merck
© Merck KGaA
Unterschiedliche Größen von vorgepackten präparativen Chromatographiesäulen der Firma Merck.