Measurement of K Vitamins in Human and Animal Plasma by High-Performance Liquid Chromatography with Fluorometric Detection

Abstract

A sensitive method for measuring endogenous vitamin K₁ (VK₁) and vitamin K₂ (MK-n) in human and animal plasma was developed based on high-performance liquid chromatography combined with coulometric reduction and fluorometric detection. The vitamins were extracted from plasma, purified with a silica Sep-Pak cartridge, and then measured by using the standard method. The detection limits of VK₁ and MK-4 were 5 pg/injection for each of the standard substances and 50 pg/ml for each of the two as components of human plasma.