title: Determination of vitamin U and its degradation products by high- performance liquid chromatography with fluorescence detection.
abstract: A high-performance liquid chromatographic method has been developed for the determination of vitamin U in tablets and capsules. Threonine was employed as the internal standard through the assay. The o-phthalaldehyde derivatives were prepared and then chromatographed isocratically on a reversed-phase C18 column. The optimum reaction time for both vitamin U and threonine at pH 10.5 is 5 min. Vitamin U and its major degradation product in the dosage forms, viz., methionine sulphoxide, were separated and quantified with a relative standard deviation of about 1%, using a fluorescence detector with excitation and emission wavelengths at 340 and 450 nm respectively. A linear relationship has been established between the peak area ratio of vitamin U/threonine and the concentration of vitamin U over the range of 2.5-50 micrograms/ml.
authors: Government Laboratory, North Point, Hong Kong.
authors: C P
authors: CP
authors: Leung
authors: W K
authors: WK
authors: Leung
mesh_terms: D002851:Chromatography, High Pressure Liquid; D008715:Methionine / Q000031:analogs & derivatives; D004364:Pharmaceutical Preparations / Q000032:analysis; D013050:Spectrometry, Fluorescence; D014814:Vitamin U / Q000032:analysis*; D014815:Vitamins
chemical_list: D004364:Pharmaceutical Preparations; D014815:Vitamins; D014814:Vitamin U; D008715:Methionine; C013111:methionine sulfoxide