SIMULTANEOUS HPLC ANALYSIS OF HYDROPHOBIC PRODRUGS AND THEIR HYDROPHILIC METABOLITES IN BIOLOGICAL MEDIA WITHOUT SAMPLE PREPARATION. APPLICATION TO THE BIOTRANSFORMATION STUDIES OF PRONUCLEOTIDES DERIVED FROM 5-FLUOROURACIL

Abstract

Improvements of an “on-line cleaning” HPLC method for analysis of biological samples are presented: (i) the use of cleaning precolumns filled with hydrophobic stationary phases instead of the hydrophilic ones previously used to eliminate the biological matrix; (ii) the combination in the mobile phase of anionic and cationic pairing reagents in order to retain on the precolumn all the metabolites, whatever their hydrophilicity and ionicity are. Such modifications allowed to study the biotransformation of prodrugs of 5-Fluorouracil, designed to act as antitumoral pronucleotides.

ACKNOWLEDGMENTS

These investigations were supported by grants from the french “Fondation pour la Recherche Médicale” (FRM) and from the french “Ligue Nationale contre le Cancer”. We thanks the Waters Company (Saint Quentin en Yvelines, France) for a generous gift of HPLC materials. We are indebted to Dr S. Peyrottes for critical review of the manuscript.