Pressure Control for Tangential Flow Filtration

Tangential flow filtration (TFF) is used in the biopharmaceutical industry as an effective and efficient method for separating and purifying biomolecules. TFF is used upstream to separate waste and target biomolecules from bioreactor broth during perfusion, and downstream in purification for target molecule clarification, buffer exchange or ultrafiltration.

During the process, the differential pressure across the TFF membrane (Trans-membrane pressure, TMP) must be maintained within a narrow range to provide the highest flux, and to prevent membrane gelling (fouling caused by retained product deposition). The Equilibar® back pressure regulator with its multi-orifice design delivers superior precision and can accurately control TMP across a wide range of flow rates. The high turn-down makes the Equilibar BPR an excellent choice in traditional transflow filtration control.

In the schematic above, Equilibar® single use back pressure regulators (BPRs) are used in both the retentate and permeate lines of the TFF process. Setpoint signals are sent to the electro-pneumatic pilot regulators from the main control system to set the pilot pressures on the Equilibar BPRs. This setup maintains a stable target pressure differential across the filter membrane for effective TFF process results.

A similar TFF setup can be configured without a BPR on the permeate line.

Equilibar single use pressure control valve was developed in response to the biopharma industry’s rapidly expanding requirements for low cost components that can be sterilized through radiation and disposed of after use. It is also appropriate for other service conditions that require single use components.

The valve’s patent pending design offers USP Class VI polymers that can be sterilized as an assembly. The Single Use Equilibar BPR features the same dome-loaded multiple orifice technology as all Equilibar patented products, delivering instantaneous control, frictionless operation, superior precision, and exceptionally wide flow rate ranges. Its strengths are particularly well suited to control the transmembrane pressure in tangential flow filtration control applications.