I need to concentrate proteins that I extract with 4% SDS and 2% b-ME? Which concentrator should I use, and has anybody tried to concentrate with these conditions and then run the proteins for western blot?
I concentrate cell supernatants with Amicon filter Units from Millipore, but my sample do not contain SDS, of course. I found them very useful, specially if your proteins to concentrate has a high mollecular weight (as the lower weight the longer it takes to centrifuge the devices for a proper protein concentration). Unfortunatley you should check if they work with samples containing SDS. Good luck!