Rapid and simple HPLC analysis of vitamin K in food, tissues and blood

The lack of precise data in food composition tables and also in human and a nimal plasma concentrations of phylloquinone and other vitamers demands int ensive investigation of both; appropriate analytical methods are necessary. Sensitive and selective detection, simplicity and rapidity of the method, and precision and reliability of the data are recommended. Based on a RP-HP LC assay using post-column derivatization and fluorescence detection, combi ned with a liquid-liquid sample clean-up, a simple and rapid assay is prese nted. The application to food, human plasma and animal tissues is shown. Th e samples cover a wide range of matrices, from those of fairly low, e.g. hu man plasma and milk, to those of high phylloquinone content, e.g. broccoli. For verification purposes mass-spectroscopy (for human plasma) or differen t fluorescence wavelengths (for the food items) were applicated. Coefficien ts of variation did not exceed 10% for any matrix and there were no remarka ble losses over the whole analytical process. The lower limit of detection for plasma samples was estimated as 0.04 ng/ml. (C) 1999 Elsevier Science L td. All rights reserved.