Analysis of vinca alkaloids in plasma and urine using high-performance liquid chromatography with electrochemical detection.

The reversed-phase high-performance liquid chromatography with electrochemical detection was used to quantify plasma and urine levels of vinblastine, vincristine, vindesine and a metabolite of vinblastine, desacetylvinblastine. Sample clean-up consisted of solid-phase extraction with a Bond Elut CN column. The extracts were separated on a Hypersil ODS column. The mobile phase consisted of a mixture of methanol and 10 mM phosphate buffer (pH 7.0). The limit of sensitivity using electrochemical detection was 100 pg on-column for all compounds with a signal-to-noise ratio of 3. Quantification of the compounds in human plasma and urine was possible down to 1 ng/ml (ca. 1 pmol). Pharmacokinetic results show that the sensitivity of the method is adequate for drug monitoring in clinical research.