A simple HPLC method with fluorescence detection for simultaneous determination of 10-methoxycamptothecin and its metabolite 10-hydroxycamptothecin in rat liver tissue.

Abstract

A simple HPLC method to determine the amount of 10-methoxycamptothecin (MCPT) and its major metabolite 10-hydroxycamptothecin (HCPT) in rat liver tissue was developed in the present study. Camptothecin (CPT) was used as internal standard (IS). A piecewise linear function was used over lower and higher concentrations, respectively. The calibration curves were linear (r (2) >0.99) over concentrations from 2.5 to 20 ng/mL and 20 to 320 ng/mL for both MCPT and HCPT. The method had an accuracy of 92.74% to 112.76%, and the intra- and inter-day precision (RSD%) were 11.85% or less for MCPT and HCPT. The stability data showed no significant degradation occurred under the experimental conditions. This method was successfully applied to the tissue distribution study of MCPT and its metabolite HCPT in liver tissue samples after intravenous administration.