Hi, If your are talking about proteins or protein subunits, this means that you are making polymers of nY, and Y becames the monomer. So in this case, I will not consider Y as an impurity. If I get you right, then size exclusion chromtography is good option to separate the monomers from the bigger polymers. Another way to do that, in my opinon, is that if you have a good estimate of the stoichometry between the monomers and polymers (and hence concentration of monomer in the cell), then run a refrence ITC with same monomer concetrate and this will automatically subtract the influence of Y component.
I hope this give the slightest hint!! Ahmed. --- On Tue, 8/24/10, Francis E Reyes <francis.re...@colorado.edu> wrote: From: Francis E Reyes <francis.re...@colorado.edu> Subject: [ccp4bb] offtopic: effect of compound impurities on ITC? To: CCP4BB@JISCMAIL.AC.UK Date: Tuesday, August 24, 2010, 11:11 AM Hi All I'm curious the effect of small impurities in commercially synthesized compounds on ITC and its analysis. Say if compound Y is the high affinity binder, but you make a derivative that differs from a single functional group from Y (you used Y to make this new compound) and you never are able to completely get rid of Y. How does this affect the analysis of determining the derivative's affinity by ITC? References or personal experience is appreciated! F --------------------------------------------- Francis E. Reyes M.Sc. 215 UCB University of Colorado at Boulder gpg --keyserver pgp.mit.edu --recv-keys 67BA8D5D 8AE2 F2F4 90F7 9640 28BC 686F 78FD 6669 67BA 8D5D