Simultaneous determination of a new anticancer drug galocitabine and its metabolites in blood by high-performance liquid chromatography

Abstract

A relatively simple and sensitive high-performance liquid chromatographic (HPLC) method is described for measuring galocitabine (Ro 09-1390) and its metabolites, i.e. 5′-deoxy-fluorocytidine (5′-DFCR), 5′-deoxy-fluorouridine (5′-DFUR) and 5-fluorouracil (5-FU), in blood for the purpose of studying pharmacokinetics and toxicokinetics in small animals. The procedure for blood includes deproteinization with acetonitrile. Blood components were separated on a reversed-phase C₁₈ column with a linear gradient of acetonitrile and water and detected at a wavelength of 270 nm. The between-day relative standard deviation (RSD) was less than 10% for all compounds at concentrations of 10–100 μg ml⁻¹. The calibration curves obtained from the analysis of blood samples were linear and the correlation coefficients ranged from 0.997 to 0.999. The calculated determination limits were 6.9 μg ml⁻¹ for galocitabine, 3.0 μg ml⁻¹ for 5′-DFCR, 4.0 μg ml⁻¹ for 5′-DFUR and 3.7 μg ml⁻¹ for 5-FU.