TCA/DOC precipitation - (Dec/06/2005 )

Hi

To precipitate proteins in minimal growth media for secretome analysis, I added Na DOC to 0.02% (4 C, 30 min) and then TCA to 10% (4 C, overnight). I got fine precipitate - so fine that half of the precipitate can not be pelleted by centrifugation at 30,000 g for 30 min. Could anyone tell me why and what I can do to improve the method? I wash the TCA precipitate with acetone, but maybe I should include acetone during TCA precipitation?

see this topic.
It may help (at least i hope so...)