1979 年 99 巻 10 号 p. 1007-1013
A high performance liquid chromatographic method was developed for the simultaneous determination of vitamin K and vitamin K oxide in biological materials. The method involves n-hexane extraction of plasma or liver homogenate and reversed phase separation on Nucleosil[○!R] C18 with a mobile phase of methanol-ethanol (7 : 3, v/v) followed by fluorometric detection of the reaction products with NaHSO3-HCl and NaBH3CN. Minimum detectable quantity was 2 ng for phylloquinone and menaquinone-4, and 3 ng for phylloquinone oxide and menaquinone-4 oxide, respectively. This method is simpler and more specific than the conventional methods for the determination of vitamin K oxide.