Purification of GST FUSION PROTEIN - (Jan/08/2009 )

Hi,
I am trying to purify GST fusion protein, but a final step requires dialysis. I expect my sample volume to be very less at the end, can anyone please tell me what procedure do I use for small size sample dialysis? and why do I need to dialyse my protein anyway?

thanks

depending on the volume you can use:

various diameter dialysis tubing (narrow for low volumes);

low volume slide-a-lyzer (pierce, now thermo);

eppendorf tube with dialysis membrane attached;

if just a few ul then you can float a dialysis membrane on top of buffer (in a beaker) and put a drop of sample on the membrane.

you dialyze to remove components that you don't want present in the next step (or in storage) and to add things that you do want.