Why does the ITC curve in an interaction between a DNA aptamer and peptide ligand have both exothermic and endothermic peaks at the same time?

I am using MicroCal ITC 200 (GE) and performing an interaction study between a DNA aptamer (12 kDa) and a peptide ligand (1.91 kDa). How can I explain an ITC curve with both negative and positive...

28 December 2017 306 4 View