Thanks everyone for your responses. I definitely plan to save the flowthrough so we'll see what happens. My protein has a His tag and I did consider doing an affinity step for concentration except I do not want to have imidazole for some functional assays that I need to carry out with the protein. Just occurred to me that I could simply dialyze out the imidazole after the affinity step.
Thanks again! Raji On Sat, Jul 13, 2013 at 8:47 PM, Raji Edayathumangalam <r...@brandeis.edu>wrote: > Hi Folks, > > Sorry for the non-ccp4 post. > > I have purified an 18kDa membrane protein and want to concentrate the > protein from gel filtration fractions, which are in buffer containing 0.05% > DDM (well above the CMC for DDM). My colleague was able to concentrate a > 30kDa membrane protein using a 100kDa MWCO concentrator but I am not sure > if I can do the same without losing protein in the flowthrough. On the > other hand, if use too low a MWCO for the concentrator, then I'm concerned > that I may end up concentrating the DDM and end up with too much detergent > in the final sample. > > Any tips about how to concentrate my low MW protein without concentrating > the DDM? > > Many thanks. > Raji > > -- > Raji Edayathumangalam > Instructor in Neurology, Harvard Medical School > Research Associate, Brigham and Women's Hospital > Visiting Research Scholar, Brandeis University > > -- Raji Edayathumangalam Instructor in Neurology, Harvard Medical School Research Associate, Brigham and Women's Hospital Visiting Research Scholar, Brandeis University
