SIMULTANEOUS DETERMINATION OF DOXORUBICIN AND IRINOTECAN IN CONJUNCTION WITH THEIR MAJOR METABOLITES BY ULTRA HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Abstract

An accurate UPLC method was developed and validated for the simultaneous determination of irinotecan and doxorubicin extracted from murine plasma, along with their major metabolites SN-38 and doxorubicinol, respectively. The parent drugs and metabolites were extracted from plasma by protein precipitation method. Camptothecin was used as the internal standard. Chromatographic separation was performed using an ACQUITY UPLC BEH C18 column (150 × 2.1 mm, particle size of 1.7 µm) at 40°C by means of gradient elution. The mobile phases for gradient elution were consisted of 0.1 % v/v formic acid in either acetonitrile or water. The flow rate was 0.5 mL/min, and the total run time was 7 min. The linear quantitation ranges for parent drugs (irinotecan and doxorubicin) and for metabolites (doxorubicinol and SN-38) were 250–10000 ng/mL and 125–5000 ng/mL, respectively (r2 > 0.99). The lower limit of quantification (LLOQ) for irinotecan and doxorubicin was 250 ng/mL, and the LLOQ for SN-38 and doxorubicinol was 125 ng/mL. The intra- and inter-day relative standard deviation was <10 %, and accuracy was >90%.