title: Liquid chromatography and fluorescence detection of vitamin A in animal feeds, finished feeds, and premixes.
abstract: A simple liquid chromatographic method for vitamin A (retinol) in animal feeds is described. The feed is saponified, diluted to minimize interferences, and extracted into petroleum ether with a single step. The analysis is sensitive and specific with liquid chromatography and a fluorescence detector. The minimum level of detection is 15 ng/mL, which is equivalent to 10,000 units/lb vitamin A. The method includes a stable and reproducible standardization of vitamin A that is used to calibrate standard peak heights in terms of units retinol/mL. Guarantees of 10,000 units/lb up to premix levels can be analyzed with good recoveries and precision.
authors.affiliation: Michigan Department of Agriculture, Laboratory Division, East Lansing 48823.
authors.forename: V A
authors.initials: VA
authors.lastname: Thorpe
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D002853:Chromatography, Liquid; D007202:Indicators and Reagents; D010602:Pharmacopoeias as Topic; D012015:Reference Standards; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D014481:United States; D014801:Vitamin A / Q000032:analysis*
chemical_list: D007202:Indicators and Reagents; D014801:Vitamin A