Buffer exchange --- dialysis tubing

1. Prepare dialysis tubing with an appropriate cut-off molecular weight. Check for instructions for the tubing type you use. If not ready to use, depending on the type, you may chose one of the following method to prepare the tubing:

  • Soak the tubing in ddH2O/0.1% sodium azide overnight.
  • Boil in ddH2O for 15 minutes.
  • Microwave in ddH2 for a few minutes. Don't allow it to boil.

    (Warning: some brand of dialysis tubing can't be boiled or cut-off may change when heated over 37 C.)

    2. Dialysis tubing can be stored at 4 C in ddH2O/0.1% sodium azide.

    3. Rinse with ddH2O thoroughly before use.

    4. Cut a tubing of the appropriate size, clip one end with a dialysis tubing clip. Test for leaks with ddH2O.

    5. Remove water, and add samples. Clip the other end.

    6. Dialysis in at least 100X volume of the buffer the sample will be exchanged into. Stir slowly with a magnetic bar. Cool the buffer before hand and dialysis at 4 C if the sample is temperature sensitive.

    7. Change the buffer every 2-4 hours for at least 3 times.

    8. Carefully remove the sample out of the tubing.