Determination of artelinic acid in blood plasma by high-performance liquid chromatography

A reversed-phase high-performance liquid chromatographic method is described for the analysis of the new antimalarial drug artelinic acid in blood plasma. The influence of mobile phase composition, pH and type of mobile phase modifier on the retention of artelinic acid on the reversed-phase column is reported. Linear calibration curves were obtained in the range 0-500 ng/ml artelinic acid. Intra-assay and inter-assay variability in the analysis of plasma samples spiked with the drug were less than or equal to 15%. Plasma samples of the drug were found to be unstable when stored at -20 degrees C, the concentration of the drug decreasing by over 50% within three days. Plasma samples stored at -70 degrees C remained stable for at least two weeks. Initial pharmacokinetic studies in the rat showed that following intravenous administration, plasma concentrations of artelinic acid declined mono-exponentially. The relatively short elimination half-life (17 +/- 5 min) of artelinic acid is consistent with what is known for qinghaosu and its derivatives.