Selectivity improvements in highly charged UF membranes Original Research Article

We have previously developed a family of charge-modified ultrafiltration membranes with greatly enhanced properties. Both yield and selectivity can be improved when using these membranes by appropriately varying solution ionic strength and pH. The technology is based on Ultracel™ PLC (composite regenerated cellulose) membranes and maintains their desirable properties of ultra-low protein binding and robust process performance. We have now developed an improved chemistry that allows us to significantly increase the ligand density and the resulting level of charge on the membrane. Higher charge is desirable to maximize the benefits of the technology. These benefits had already been shown using membranes with lower charge densities. Significantly, it has been shown that critical process steps in monoclonal antibody purification processes can be replaced or even eliminated by using an ultrafiltration step with charged membranes.