Gel Compression Considerations for Chromatography Scale-Up for Protein C Purification

Abstract

This work is to establish theoretical and experimental relationships for the scale-up of Immobilized Metal Affinity Chromatography (IMAC) and Immuno Affinity Chromatography for the low cost production of large quantities of Protein C. The external customer requirements for this project have been established for Protein C deficient people with the goal of providing prophylactic patient treatment. Deep vein thrombosis is the major symptom for protein C deficiency creating the potential problem of embolism transport to important organs, such as, lung and brain.

Gel matrices for protein C separation are being analyzed to determine the relationship between the material properties of the gel and the column collapse characteristics. The fluid flow rate and pressure drop is being examined to see how they influence column stability. Gel packing analysis includes two considerations; one is bulk compression due to flow rate, and the second is gel particle deformation due to fluid flow and pressure drop.

Based on the assumption of creeping flow, Darcy’s law is being applied to characterize the flow through the gel particles. Biot’s mathematical description of three-dimensional consolidation in porous media is being used to develop a set of system equations. Finite difference methods are being utilized to obtain the equation solutions. In addition, special programs such as finite element approaches, ABAQUS, will be studied to determine their application to this particular problem.

Experimental studies are being performed to determine flow rate and pressure drop correlation for the Chromatographic columns with appropriate gels. Void fraction is being measured using pulse testing to allow Reynolds number calculations. Experimental yield stress is being measured to compare with the theoretical calculations.

Total Quality Management (TQM) tools have been utilized to optimize this work. For instance, the “Scatter Diagram” has been used to evaluate and select the appropriate gels and operating conditions via Taguchi techniques. Targeting customer requirements under the structure of TQM represents a novel approach to graduate student research in an academic institution which is designed to simulate an industrial environment.

This project has been supported by The Whitaker Foundation under a “Special Opportunity Award”, the American Red Cross, and Hillis-Carnes corporation.