Spin dialysis is used for quick exchange of the buffer. It represents an
alternative to phenol extraction followed by ethanol precipitation. The
solution is applied on a small column of sephacryl with a small exclusion volume.
- Prepare the column. Poke a small opening into the tip of a 500 µl reaction
vial with a canula. Do not push the tip of the canula through the plastic. Fill
in small glass beads to seal the opening.
- Fill in 500 µl of Sephacryl-S200 suspended in
the buffer of choice.
- Put the small column into a 2 ml reaction vial and spin at 2000 rpm for 1 min. Discard the
flow-through. Make sure that no beads are in the flow-through.
- Carefully pipette the solution onto the gel bed. Spin at 2000 rpm for 2 min. Collect the
flow-through in a new 1,5 ml reaction vial. Discard the column
Beads: Sephacryl S-200 (stored at 4¡C in 20% ethanol) gently suspend the gel and transfer 15 ml to a
20 ml falcon vial. Spin briefly at low speed, discard the supernatant and suspend in the buffer
of choice (e. g. TE or Tris+100 mM NaCl).
Repeat twice.
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