Maybe you should give us a hint about the identity of your protein (if you dare....;-)). I'm sure there are folks around who may be able to say whether or not your protein is supposed to be brown. You can't expect too much help if you don't provide (m)any details.
Cheers, Bert On 9/24/10 4:34 AM, "sandeep" <toskgu...@rediffmail.com> wrote: Dear all, I have purified protein from E.coli. expression system. the protein has been purified with three independant columns. Now during concentration step using amicon, the protein shows brown colour. what could be the reason. best regards and Thanks, sandy <http://sigads.rediff.com/RealMedia/ads/click_nx.ads/www.rediffmail.com/signatureline....@middle?>
