Cell and gene therapy, new vaccines and the production of monoclonal antibodies are the most dynamic areas in the biopharmaceutical industry. Their use in research and development, in diagnostics and therapeutic treatments has required complex, multi-stage purification processes to date, using separation columns that are costly and slow.
Chromatographic membranes have increasingly gained ground as an alternative to separation columns. This is because they achieve higher flow rates and an effective transfer of mass. Biomolecules, which are adsorbed through their positively or negatively charged binding sites, can however only be recovered by means of larger changes in pH values or through high salt concentrations in the rinsing fluid, which may compromise delicate biomulecules or be difficult to control in order to maximize yield and prevent ‘bleed’ or mixing of the product of importance with other substances.
Digital membrane chromatography ingeniously solves this challenge: By positioning a chromatographic membrane between two gold-coated membranes, an electric field is generated by applying a voltage across the gold layer. This electric field is used to elute biomolecules bound to the chromatographic membrane. The use of salts in AEX or CEX or a shift in the pH value in protein A membranes is no longer necessary. Membrane chromatography is going digital.