One of the other things you need to be concerned about with thermal melts is the change in buffer pKa as temperature varies (I seem to remember this being called the "beta" factor). Phosphate is used for CD melts regularly because its pKa is fairly invariant with temperature. (A good reference is "Data for Biochemical Research" by Dawson, Ch. 18). Acetate also shares this invariance but the Good buffers often do not. This is of course a concern with the Spyro Orange experiment as well.
Matthew Merski Shoichet Group UCSF
