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Removing proteins by dialysis - want to get rid of proteins in a vesicle suspension (Sep/26/2007 )

Hi

My sample contains large vesicles (5-10┬Ám) and proteins in the surrounding solution.
I would like to get rid of the proteins as good as possible. the vesicles are quite prone to rupturing, therefore
I'd like to avoid ultracentrifugation. when centrifuging I could see that they tend to aggregate , which is something I want
to avoid as well.

There are dialysis membranes that have a cutoff of 300kDa and 1000kDa - Is this cutoff high enough or are
there smarter methods to do this?


thanks in advance!

-gluehwein-

I think with vesicles of this size range, you dont need such high speed to spin it down. column separation is another option. Dialysis may be very slow for proteins. Protease digestion could be an alternative as well.

-genehunter-1-

QUOTE (gluehwein @ Sep 27 2007, 12:21 AM)
Hi


There are dialysis membranes that have a cutoff of 300kDa and 1000kDa - Is this cutoff high enough or are
there smarter methods to do this?


thanks in advance!

How large are the contaminating proteins?I would guess you want the dialysis pores to be at least the same size as the largest protein. (I say this reversing the criteria for dialysing proteins, whereby you want a pore size about 3 times smaller than the protein of interest)

-swanny-