Advantages of Protein A Membrane Chromatography: High Productivity, Strong Impurity Removal Capability, and More

Protein A affinity chromatography is the gold standard for antibody purification. In practice, it is mainly performed using resin-based packed bed columns. However, for porous resins, mass transport depends on slow diffusion and, consequently, low flow rates/long residence times are required to achieve decent binding capacities (i.e., >30 mg/mL), which leads to long processing time and low productivity. Recently, Protein A membranes have emerged as a promising alternative to Protein A columns. Membrane adsorbers, which have large pores, enable convection-based mass transport and allow high dynamic binding capacity to be achieved at a relatively short residence time (on the order of seconds). Hence, Protein A membranes can be operated at high flow rates and gain significantly improved productivity. In addition to high productivity, we recently found that Protein A membranes possess a much stronger impurity-removing capability than Protein A columns. This review introduces the advantages that Protein A membrane chromatography offers, especially those that have not been well recognized before. These advantages allow high-quality products to be obtained with significantly reduced costs.