Development and validation of a bioanalytical assay for (E)-5-(2-bromovinyl)-2 '-deoxyuridine in plasma by capillary zone electrophoresis

A capillary zone electrophoretic method for the quantification of (E)-5-(2- bromovinyl)-2'-deoxyuridine in plasma has been developed and validated. Sep aration was performed with a 25 mmol/l berate buffer, pH 9.0, after an init ial rinsing step with sodium hydroxide. The rinsing step was necessary for reproducible analyses of aqueous samples and plasma extracts obtained by C- 18 solid-phase extraction after deproteination with perchloric acid. No int erferences with plasma compounds were observed. The calibration graph was l inear over the range of 30 to 3000 ng/ml using 5-fluorouracil as external s tandard. The limit of quantification was 24 ng/ml. The CZE method is fast, reproducible, linear and is therefore a good alternative for the already es tablished HPLC methods. (C) 1999 Elsevier Science BN. All rights reserved.