Determination of chlorzoxazone and 6-hydroxychlorzoxazone in human plasma and urine by high-performance liquid chromatography.
A sensitive and reproducible method is described for the determination of the cytochrome P450 enzyme 2E1 substrate chlorzoxazone and its primary metabolite 6-hydroxychlorzoxazone in human plasma and urine. Plasma or diluted urine were acidified, incubated with beta-glucuronidase and then were extracted with diethyl ether. Separation of the analytes was achieved on a C18 column with UV detection set at 283 nm. Excellent linearity was observed over the concentration ranges of 100-3000 ng/ml and 4-400 micrograms/ml in plasma and urine, respectively. The intra-assay variability was < or = 5.1% and the inter-assay variability was < or = 8.2% for each compound in each matrix. The method presented is applicable to pharmacokinetic and pharmacogenetic studies utilizing chlorzoxazone.
Frye
R F
RF
Department of Pharmacy and Therapeutics, School of Pharmacy, University of Pittsburgh Medical Center, University of Pittsburgh, PA 15261, USA.
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D002753:Chlorzoxazone / Q000031:analogs & derivatives* / Q000032:analysis* / Q000097:blood / Q000652:urine; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet
C039289:6-hydroxychlorzoxazone; D002753:Chlorzoxazone