Leung C P, Leung W K
Government Laboratory, North Point, Hong Kong.
J Chromatogr. 1989 Oct 6;479(2):361-7. doi: 10.1016/s0021-9673(01)83351-3.
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.
已开发出一种高效液相色谱法用于测定片剂和胶囊中的维生素U。通过该测定法使用苏氨酸作为内标。制备邻苯二甲醛衍生物，然后在反相C18柱上进行等度色谱分离。维生素U和苏氨酸在pH 10.5时的最佳反应时间均为5分钟。使用激发和发射波长分别为340和450 nm的荧光检测器，分离并定量了剂型中的维生素U及其主要降解产物，即甲硫氨酸亚砜，相对标准偏差约为1%。在2.5-50微克/毫升范围内，已建立了维生素U/苏氨酸的峰面积比与维生素U浓度之间的线性关系。
