Enantiomer separation of flavour and fragrance compounds by liquid chromatography using novel urea-covalent bonded methylated β-cyclodextrins on silica

A novel methylated beta-cyclodextrin chiral stationary phase (CSP-ME), which was chemically immobilised onto porous silica via multiple urea-linkages was synthesised. The CSP-ME chiral stationary phase depicted good enantiomer separation abilities for some well-known flavour as well as fragrance compounds using high-performance liquid chromatography under reverse phase conditions. The optimum resolution for alpha-ionone, 3-methyl-alpha-ionone, flavanone, 5-methoxyflavanone, 6-methoxyflavanone, 7-methoxyflavanone, hesperetin, naringenin and taxifolin was achieved using a mobile phase composition consisting of 1 wt.% triethylammonium acetate buffer (pH 4.68)-methanol. The effects of pH of tri-ethylantmonium acetate buffer and the methanol-acetonitrile content of the mobile phase composition on their retention time and resolution were examined to optimise the separation conditions. (C) 2002 Elsevier Science B.V. All rights reserved.