Problems in His-tag protein purification with TALON - (Jun/02/2009 )

I am currently trying to purify a membrane His-tag protein from HeLa cells. I have no problem to pull it down by TALON resin. The western blot show very clear band. However, I have problem on Blue staining on this protein (since I want to send the sample for MS proteomics).

I use only 1% of the pull-down products for western, I can see the band. But the protein can not be detected by Blue staining, on the contrary, I saw many other bands in the blue staining. It is wired to me because even the sensitivity between these two methods have 100 folds diffrence, I should be able to see the bands in blue staining, should I?

Did anyone meet such kind of problem before? I use NP40 buffer as the TALON pull-down buffer.

BTW, could any one provide me the recipe of Clontech TALON xTractor buffer?

Many thanks!