Resolution of ￥a-Amino Acids on a Chiral Stationary Phase Based on (+)-(18-Crown-6)-2,3,11,12-tetracarboxilic Acid without Extra Free Aminopropyl Groups on Silica Surface: the Effect of Ammonium Ion Mobile Phase Modifier on the Resolution Behaviors

摘要

A liquid chromatographic chiral stationary phase (CSP) based on (+)-(18-crown-6)-2,3,11,12-tetracarboxilic acid without extra free aminopropyl groups on silica surface has been demonstrated to be quite effective for the resolution of various モ-amino acids. The retention factors (k₁) for the resolution of モ-amino acids on the CSP were quite large and the large retention factors might be quite attractive along with the reasonable separation factors (メ) for preparative scale enantioselective chromatography. The large retention factors on the CSP were found to be reduced effectively by adding ammonium ion to mobile phase without sacrificing the chiral recognition efficiency of the CSP. Consequently, the CSP is also quite applicable for use in analytical enantioselective chromatography.