title: Analysis of all-rac-alpha-tocopheryl acetate and retinyl palmitate in medical foods using a zero control reference material (ZRM) as a method development tool.
abstract: A liquid chromatographic method is described for analysis of all- rac-alpha-tocopheryl acetate and retinyl palmitate in medical food. The vitamins are extracted in isopropyl alcohol and hexane-ethyl acetate without saponification and quantitated by normal-phase chromatography with fluorescence detection. All rac-alpha-tocopheryl acetate and retinyl palmitate are chromatographed isocratically with a mobile phase of 0.5% (v/v) and 0.125% (v/v) isopropyl alcohol in hexane, respectively. Recovery studies performed on a medical food zero control reference material (ZRM) fortified with the analytes averaged 99.7% (n = 25) for retinyl palmitate and 101% (n = 25) for all- rac-alpha-tocopheryl acetate. Coefficients of variation were 0.87-2.63% for retinyl palmitate and 1.42-3.20% for all-rac-alpha-tocopheryl acetate. The method provides a rapid, specific, and easily controlled assay for analysis of vitamin A and vitamin E in medical foods. Use of chlorinated solvents is avoided.
authors.affiliation: U.S. Food and Drug Administration, Atlanta Center for Nutrient Analysis, Atlanta, GA 30309, USA.
authors.forename: G W
authors.initials: GW
authors.lastname: Chase
authors.forename: R R
authors.initials: RR
authors.lastname: Eitenmiller
authors.forename: A R
authors.initials: AR
authors.lastname: Long
mesh_terms: D002845:Chromatography / Q000379:methods; D004224:Diterpenes; D005526:Food, Formulated / Q000032:analysis*; D007225:Infant Food / Q000032:analysis; D011786:Quality Control; D012015:Reference Standards; D000084562:Retinyl Esters; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism; D024505:Tocopherols; D014801:Vitamin A / Q000031:analogs & derivatives* / Q000032:analysis; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000032:analysis; D024502:alpha-Tocopherol / Q000031:analogs & derivatives*
chemical_list: D004224:Diterpenes; D000084562:Retinyl Esters; D014801:Vitamin A; D014810:Vitamin E; C014794:retinol palmitate; D024502:alpha-Tocopherol; D024505:Tocopherols