Highly Efficient Process For The Purification Of IgG

By Sheldon Broedel, Jr., Mike McManaway, and William Barrett

Protein A chromatography remains a bottleneck in downstream processing. There is often a tradeoff between resin capacity utilization and processing speed with the choice of effecting the economics of the process. Due to the small pore sizes of traditional resins, mass transfer raters reduce the overall binding kinetics between Protein A and IgG. Consequently, slower flow rates are needed to ensure capture of the IgG molecule. In contrast, membrane metrices are microporous and the overall binding kinetics is determined by the protein-protein kinetics and not on mass transfer. Thus, membrane chromatography can be run at higher flow rates.

In this paper we review a unique Protein A column that uses an expanded polytetrafluoroethylene membrane composite that offers high binding capacity at high flow rates.