title: Simultaneous determination of vitamins A and E and carotenoids in plasma by reversed-phase HPLC in elderly and younger subjects.
abstract: A reversed-phase high-performance liquid-chromatographic method for the simultaneous determination of retinol, alpha-tocopherol, alpha-carotene, beta-carotene, cryptoxanthin, lutein/zeaxanthin, and lycopene is described. This method was applied to plasma measurements in healthy young and elderly subjects. The plasma, deproteinized with ethanol, is extracted twice with n-hexane. After evaporation, the residue is dissolved in 50 microL of tetrahydrofuran and made up to 200 microL with ethanol. Samples (50 microL) are injected onto a 250 x 4.6 mm column of 5-microns-particle Spherisorb ODS1 (Phase Separations) that had been equilibrated with solvent mixture A:B (90:10 by vol) [A = 100 mmol/L ammonium acetate in methanol: acetonitrile (80:20 by vol) and B = 100 mmol/L ammonium acetate in water] at 2 mL/min. The analytes are eluted by running a 12-min linear gradient to 100% A; solvent A is then maintained for 10 min. Intrabatch CVs were 2.3%, 3.3%, 2.8%, 3.6%, 3.6%, and 3.0% for retinol, alpha-tocopherol, lutein/zeaxanthin, cryptoxanthin, lycopene, and beta-carotene, respectively. The corresponding interbatch CVs were 4.9%, 5.8%, 12.3%, 6.5%, 8.0%, and 3.4%.
authors.affiliation: Department of Chemical Pathology, Central Middlesex Hospital, London, UK.
authors.forename: Z
authors.initials: Z
authors.lastname: Zaman
authors.forename: P
authors.initials: P
authors.lastname: Fielden
authors.forename: P G
authors.initials: PG
authors.lastname: Frost
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002338:Carotenoids / Q000031:analogs & derivatives / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D065366:Cryptoxanthins; D004355:Drug Stability; D005260:Female; D006801:Humans; D014975:Lutein / Q000097:blood; D000077276:Lycopene; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D014801:Vitamin A / Q000097:blood*; D014810:Vitamin E / Q000097:blood*; D024341:Xanthophylls; D019207:beta Carotene
chemical_list: D065366:Cryptoxanthins; D024341:Xanthophylls; D019207:beta Carotene; D014801:Vitamin A; D014810:Vitamin E; D002338:Carotenoids; C041635:alpha-carotene; D000077276:Lycopene; D014975:Lutein