In article <mailman.239.1335827494.3456.meth...@net.bio.net>, novalidaddr...@nurfuerspam.de says... > > Hi Pow, long time no see :) > > My big problem is that there is almost no protein in the sample -> Iwon't see any bands. I expect about 1mg from 50 ml. I have started with 50ml of fruit juice concentrate, diluted with 50ml water and then added ammonium sulfate until saturation: No visible turbidity, No (visible) pellet after 2hrs @ 4000g (except some ammonium sulfate crystals. Unfortunately, I do not have access to a high speed centrifuge for such volumes. Spinning 24 eppis with 2ml each @ 15.000g in my small benchtop centrifuge might be an option, however. > > Could it make sense to add some unrelated protein, eg BSA or OVA > (that's what I have in my fridge), as co-precipitant (like one does > with glycogen or poly-acrylamide for DNA)?. > > Wo
Hi, what Wo presumably was referring to was a self-forming gradient (similar to CsCl). This can be done, but requires an ultracentrifuge. In your situation, I would try either dialysis against high MW PEG or an Amicon pressure cell to remove most of the sugar and fluid. You could even dilute the product of such an operation with buffer and repeat. _______________________________________________ Methods mailing list Methods@net.bio.net http://www.bio.net/biomail/listinfo/methods