RAPID SCREENING OF TAXOL METABOLITES IN HUMAN MICROSOMES BY LIQUID-CHROMATOGRAPHY ELECTROSPRAY-IONIZATION MASS-SPECTROMETRY

Liquid chromatography with an electrospray ionization (ESI) interface has been applied to study the anticancer drug taxol and its metabolite s after incubation with human hepatic microsomes. The parent drug and its metabolites were monitored in the positive-ionization mode. Since ESI gave only quasi-molecular ions for taxol and its analogues, collis ion-induced dissociation experiments were carried out in order to gene rate fragment ions, by increasing the cone voltage at the ESI source. The product-ion mass spectra of taxol and its metabolites contained di agnostic fragment ions, which enabled the presence of hydroxylated and deacetylated metabolites of taxol to be established.