Protein precipitation using Methanol/Chloroform - (Mar/24/2006 )

Hi, I am trying to precipitate a protein that is dissolved in a salt (Tris) buffer with acetonitrile using the methanol/chloroform method. When I perform the method and get a pellet, is the pellet just protein or is there also salt in the pellet? I am trying to eliminate the salt from the protein solution. Thanks.

Dialysis against water or use an Amicon system a low molecular weight cut-off membrane. It all depends on the size of your protein. You could even use gel filtration to desalt sample and precipitate selected fractions as they are eluted