protein precipitation

[Dr Engelbert Buxbaum]

s.hannier at abdn.ac.uk wrote:

> 
> I would like to concentrate a sample of proteins with less than 1 ug 
> (aout 900ng) in 1ml. What is the best precipitation method to use for a
> maximum recovery? I have heard about deoxycholate/TCA but it seems that
> recovery is 50% , which is not very good. Any advice?

Chloroform/Methanol (Wessel & Flügge) or phenol (Sauve et al) can
precipitate small amounts of protein with near complete recovery. In my
experience however proteins may be difficult to re-dissolve, but I am
working with big transmembrane proteins, so your milage may vary.