How is better to interpret kinetic data? Is it more realable a
global and simultaneous fittiong of the curves or a separate one, curve by
curve? I tried to use both but I obtained very different results.
I would say that a global fit is better than a fit obtained by separatly fitted curves of different concentrations. Another advantage is that you need less time for the analysis.
What you can do is to compare KD's calculated from the obtained kon,koff with the one determined by equilibrium analysis (e.g. by Scrubber).
This may validate one of the methods.