Résumé : A selective and sensitive reversed-phase liquid chromatographic method with electrochemical detection for the analysis of doxorubicin, daunorubicin and some of their metabolites in plasma is reported. A mobile phase consisting of acetonitrile-phosphate buffer solution-tetrahydrofuran (25-71,5-3.5) flowing at 1 ml/min through a Lichrocart RP 18 column was employed. The influence of various parameters on the separation (solvent composition, pH, tetrahydrofuran content) has been examined. An extraction of anthracyclines from plasma was performed using chloroformethanol mixture (4: 1) with high extraction efficiency; reproducible results were attained by working with a 1 M phosphate buffer which ensured a real buffering of the plasma samples. The sensitivity of amperometric detection makes this method suitable for analyzing small amounts of the parent drugs and their metabolites. The precision was better than 4% in the range 0.2 to 5 pg/ml plasma. © 1987, Taylor & Francis Group, LLC. All rights reserved.