EFFECT OF THE CHAIN MOBILITY OF POLYMERIC REVERSED-PHASE STATIONARY PHASES ON POLYPEPTIDE RETENTION

The resolution of polypeptides in reversed-phase chromatography can be improved by inducing conformational changes in the solute. Protein un folding can be achieved by an increased accessability of the hydrophob ic stationary phase. We elucidated how far results from CP/MAS solid-s tate NMR relaxation measurements could be correlated with chromatograp hic data in terms of protein and peptide retention. The retentivity an d denaturation potential of reversed stationary phases is controlled n ot only by their hydrophobicity but also by their ligand mobility and steric properties. As a consequence, we developed a simplified model f or protein retention on stationary phases with different dynamic prope rties: We used an n-octadecyl phase (RP18), a poly(octadecyl methacryl ate) phase (POMA), and a polybutadiene phase (PBD).