Submitted to: International Symposium on High Performance Liquid Phase Separations
Publication Type: Abstract Only
Publication Acceptance Date: 6/22/1997
Publication Date: N/A
Technical Abstract: Tocotrienols (lipid antioxidants) occur in plants as a complex mixture of 2-methyl-6-chromanol homologues and aromatic ring position isomers. Accurate analyses of these substances provide useful information on the antioxidant levels in vegetable oils. We wish to report the first separation of all 16 isomers of tocotrienols by reversed-phase HPLC with fluorescence detection. Individual samples of alpha-, beta-, gamma-, and delta-tocotrienols were analyzed with a reversed phase column. From an alternative approach, reversed-phase HPLC of the tocotrienol mixture on a polymer phase resulted in complete resolution of the 16 subcomponents. HPLC of the antioxidant mixture on a perfluorinated hydrocarbonaceous silica phase led to the separation of 14 subcomponents along with two other isomeric species that remained unresolved. Generally, acetonitrile mobile phases appeared to provide superior column efficiency for the separation of the title geometric isomers. The HPLC results are delineated in the context of combined effects of stationary phases and mobile phases on analyte retention and component resolution.