Why is i3 Membrane developing digital membrane chromatography?

The manufacture of monoclonal antibodies is the most dynamic area of the biopharmaceutical industry. Use thereof in R&D, diagnostics and therapeutic applications demands complex, multi-level purification processes involving separation columns which are capital-intensive and have limited scalability. For some time now, so-called chromatographic membranes have established themselves as alternatives to separation columns. These feature positively or negatively-charged binding sites which enable higher flow rates compared to separation columns and an effective mass transfer. Biomolecules adsorbed through these binding sites can only be recovered by means of greater shifting of the pH value or high concentrations of salinity in the carrier fluid. Desorption is therefore the same as separation column chromatography.

Digital membrane chromatography represents a new dimension of separation technology: the chemical binding characteristics of the stationary phase are switchable via electric potential controls enabling the separation of selected biomolecules. This means that both adsorption and desorption are by means of a simple potential regulator. Unlike conventional membrane chromatography, antibody purification or even endotoxin concentration is possible without extensive use of buffer solutions or salinity. Digital membrane chromatography displays comparable binding capacities to those of conventional membrane chromatography.

Digital separation technology offers all of the advantages of membrane chromatography compared to column chromatography:

  • scalable single-use products (from syringe filter units to m2 filter modules)
  • high flow rates and binding capacities (extensive pore structure for effective mass transfer)
  • low operating costs (high flows, low media consumption and operating pressures)


 What makes digital membrane chromatography so unique?

The combination of chemically-modified microfiltration membranes and physical potential control of the conductive membrane surface leads to significant advantages:

  • Defined adaptation of the membrane binding characteristics within seconds
  • Specific potential control for selective sampling, concentration and purification
  • Stable electrolyte behavior
  • Conservation of valuable target molecules and auxiliaries (e.g. protein A)
  • High number of adsorption and desorption steps without impairing the binding capacity


In developing innovative membranes and highly-selective separation techniques, i3 Membrane cooperates with various research facilities, such as:

  • Technical University, Munich
  • Helmholtz Center, Dresden-Rossendorf
  • Leibniz Institute, Leipzig