Determination of daunorubicin, doxorubicin and their fluorescent metabolites by high-pressure liquid chromatography: plasma levels in DBA2 mice.

A rapid and nondestructive analytic method has been developed to separate and quantitate daunorubicin, doxorubicin, and their metabolites in biological fluids. This method combines the efficiency of high-pressure liquid chromatography and the sensitivity of fluorescence monitoring. The drug plasma levels achieved after IV administration of either daunorubicin or doxorubicin at 7 mg/kg into DBA2 mice were studied. The plasma disappearance curves are biphasic with a half-life of 1 min for the first elimination phase. In urine extracts, 13-hydroxy derivatives represent 80% of the fluorescence after injection of daunorubicin and only 4% after administration of doxorubicin.