If you can find a dialysis membrane that is small enough (they have
1000 MWCO, I believe) put your 20mls into a bag and lay it on dry
PEG-8000 wrapped in Saran Wrap and foil. Pop it into the fridge for
a few hours and let the PEG suck out the water. Not sure what it'll
do in terms of the salt, but you could always just then dialyze it
against some buffer for your next step.
Why not use HPLC? If it is that small, you might be able to take
advantage of a size-exclusion column or C18...
Have fun,
--
- Christopher
"People who don't fight the unjust condemnation of others
but internalize it are, Miss Manners admits, badly in need of
lessons in self-esteem." -Judith Martin (aka Miss Manners)
cdcilley at oxytricha.mit.edu
--
- Christopher
"People who don't fight the unjust condemnation of others
