[Determination of retinol and alpha-tocopherol in milk and milk products using high-pressure liquid chromatography after saponification in serum vials].
An improved procedure is described for the determination of retinol and alpha-tocopherol in milk and dairy products using high-pressure liquid chromatography (HPLC). Samples are saponified in sealed 10-ml serum vials in the absence of oxygen, cooled and neutralized by injecting glacial acetic acid into the system. Retinyl acetate and 5,7-dimethyltocol respectively are used as the internal standards. The solution is extracted with hexane and the organic phase is cleaned up on a sodium sulphate/aluminium oxide column. The solution is evaporated under vacuum and dissolved in ethanol for HPLC analysis. A short reversed-phase column packed with RP-18, using methanol as the eluent, allows fast separations of both the vitamins.
Bilic
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N
Eidgenössische Forschungsanstalt für Milchwirtschaft, Liebefeld-Bern, Schweiz.
Sieber
R
R
D000818:Animals; D002417:Cattle; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003611:Dairy Products / Q000032:analysis*; D005260:Female; D007202:Indicators and Reagents; D008892:Milk / Q000032:analysis*; D014801:Vitamin A / Q000032:analysis*; D014810:Vitamin E / Q000032:analysis*
D007202:Indicators and Reagents; D014801:Vitamin A; D014810:Vitamin E
Bestimmung von Retinol und alpha-Tocopherol in Milch und Milchprodukten mit Hilfe der Hochdruck-Flüssigchromatographie (HPLC) nach Verseifung in Serumfläschchen.