Tangential Flow/Diafiltration

Tangential Flow/Diafiltration

SOP for Pall Filtron Tangential Flow Diafiltration Apparatus

Preparation for Start Up

  1. Make sure that the speed dial is set at zero and that the forward/reverse switch is in the "OFF" position.
  2. Turn the To Pump Valve and Back Pressure Valve to the open position (parallel to the valve body).
  3. Make sure that the 3-Way Valve is in the closed position (pointing towards the reservoir).

Cleaning the System

  1. Prepare 1 Liter of 0.1M NaOH.
  2. Pour 500ml of 0.1M NaOH into reservoir
  3. Check the pH of distilled water to be used later.
  4. Flip the forward/reverse switch to the forward position and slowly turn the speed dial to 4.
  5. Slowly turn the Back Pressure Valve toward the closed position until the pressure reads between 20-35 psi. This generates the flow rate.
  6. Drain 250 ml and make sure pH is less than 11.
  7. Turn the speed setting to zero.
  8. Open the Back Pressure Valve and close the 3-Way Valve.
  9. Turn the pump on and set the speed dial between 1-3 for a low recirculation rate for 5 minutes.
  10. Turn the speed dial to zero and open the 3-Way Valve. Recheck ph to make sure it is greater than 11.
  11. Clean the system using Deionized water by repeating steps 1-10.

Sample Filtration

  1. Add sample to be processed to reservoir, not more than 500 ml.
  2. Open the Back Pressure Valve. Be sure that the 3-Way Valve is closed (pointing toward the reservoir).
  3. Put the forward/reverse switch in the forward position and slowly turn the speed dial to 3.
  4. Slowly turn the Back Pressure Valve to the closed position until the pressure gauge reads between 20-35 psi.
  5. Continue this operation until the desired concentration is achieved. For example, 400 ml concentration to 200 ml.
  6. Once the sample size is cut in half, attach tubing to top of lid and place other end in a waste beaker for buffer exchange. Check pH to get the same as the equilibration buffer.
  7. Once an equal pH is achieved, collect the results to be used in running a column. (see Concentrate Recovery).

Concentrate Recovery

  1. When the final concentrate is achieved, turn the speed dial to zero.
  2. Fully open the 3-Way Valve.
  3. Turn the pump on and adjust to a speed setting between 1-3.
  4. Collect the concentrate that will go to the reservoir.
  5. Turn the speed back to zero, close the 3-Way Valve and return the speed dial setting to 1-3.
  6. Repeat steps 2-5 for maximum recovery.


  1. Store by following the cleaning section without rinsing the system in deionized water, use 0.1M Sodium Hydroxide as a storage agent.

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