Quantitation of oxcarbazepine and its metabolites in human plasma by micellar electrokinetic chromatography.
A reliable micellar electrokinetic chromatographic method for the determination of oxcarbazepine and its two main metabolites, 10-hydroxycarbamazepine and 10,11-trans-dihydroxy-10,11-dihydroxycarbamazepine, in human plasma was developed. The separation and determination of the analytes was achieved using a system consisting of 60 mM SDS in phosphate buffer (30 mM, pH 8.0), to which 20% (v/v) methanol was added. Separation was carried out in an uncoated fused-silica capillary with a separation voltage of 25 kV and currents typically less than 40 microA. Spectrophotometric detection was at 205 nm. Isolation of oxcarbazepine and its metabolites from plasma was accomplished by a solid-phase extraction procedure. The mean extraction yield of the analytes from plasma was higher than 94%. The linear correlation coefficients were better than 0.994 for all analytes. The limit of detection was 0.05 microg/mL, the limit of quantitation 0.15 microg/mL. The repeatability for the spiked blank plasma samples was lower than 1.9% and the intermediate precision lower than 2.1%, both expressed as RSD%. The results obtained analysing real plasma samples from epileptic patients under therapy with Tolep were satisfactory in terms of precision, accuracy and detectability.
Pucci
Vincenzo
V
Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
Kenndler
Ernst
E
Raggi
Maria Augusta
MA
D000927:Anticonvulsants / Q000097:blood*; D001711:Biotransformation; D002138:Calibration; D002220:Carbamazepine / Q000031:analogs & derivatives* / Q000097:blood*; D020374:Chromatography, Micellar Electrokinetic Capillary; D004338:Drug Combinations; D006801:Humans; D007202:Indicators and Reagents; D000078330:Oxcarbazepine; D012015:Reference Standards; D015203:Reproducibility of Results; D012967:Sodium Dodecyl Sulfate; D013501:Surface-Active Agents
D000927:Anticonvulsants; D004338:Drug Combinations; D007202:Indicators and Reagents; D013501:Surface-Active Agents; D002220:Carbamazepine; D012967:Sodium Dodecyl Sulfate; D000078330:Oxcarbazepine