Three new chiral stationary phases with different lengths of L-phenylalanine peptide were prepared by solid-phase synthesis with Boc-L-phenylalanine on silica. The effect of phenylalanine peptide length on enantioselectivity was studied. The best separation of R/S-warfarin was achieved by the chiral stationary phase with intermediate peptide length. These stationary phases were found to exist mainly in -helical conformation by using FT-IR spectra. The end-capping reagents for the N-terminus of the peptide were also evaluated.3

A new class of chiral stationary phases (CSP) with peptide chiral selectors was prepared by solid-phase synthesis with a tert-butoxycarbonyl-L-amino acid on silica. The type of amino acid that is favorable for this class of CSP is discussed. Using the CSP with the phenylalanine peptide selector, the effect of peptide length on the enantioselectivity was investigated in normal-phase mode. The applicability of the CSP with a phenylalanine peptide to chiral ligand-exchange chromatography was also examined.

Characteristic of chiral stationary phase (CSP) with poly(L-phenylalanine) peptide selector, which is in -helical state, was reported. Since environmental factors affect peptide conformation, the changes of enantioselectivity were examined depending on column temperature and mobile phase conditions (ionic strength, pH, mobile phase composition). Column temperature and pH drastically affected the enantioselectivity.Based on these changes, the relation between chiral recognition and secondary structure of the peptide selector was discussed. The column stability during sequential analysis under different separation conditions was also evaluated.