Isoentropic and isoenthalpic temperatures of protein unfolding in hydrophobic interaction chromatography

The thermal behaviors of five proteins in hydrophobic interaction chromatography (HIC) were investigated in the temperature range from 0 to 50 degrees C. The thermodynamic parameters (Delta H degrees, Delta S degrees, Delta C-p degrees and Delta G degrees) of these proteins in the process of retention and unfolding were determined. The existence of enthalpy and entropy convergence with temperature was confirmed. The differences of the isoentropic and isoenthalpic temperatures for protein unfolding in HIC system from the traditional solution were elucidated.