Kinetics of Angiotensin I alteration of conformation on different hydrophobic interaction chromatographic surfaces

► Angiotensin I used as model peptide to assess on-column alteration of conformation. ► 1st and 2nd moments of elution profiles employed to evaluate rate constants for Ang I isomerization. ► Activation energies calculated for Ang I isomerization under different conditions. ► The stationary phase catalyzes Ang I cis-trans isomerization. ► Catalysis is dependent on hydrophobic interaction ligand nature.