title: Determination of chlorzoxazone and 6-hydroxychlorzoxazone in plasma by gas chromatography--mass spectrometry.
abstract: A gas chromatographic-mass spectrometric method is presented which allows the determination of chlorzoxazone and 6-hydroxychlorzoxazone after derivatization with the reagent N-tert.-butyldimethylsilyl-N-methyltrifluoroacetamide. No interference was observed from endogenous compounds following the extraction of plasma samples from six different human subjects. The standard curves were linear over a working range of 20 to 4000 ng/ml and of 20 to 1000 ng/ml for chlorzoxazone and 6-hydroxychlorzoxazone, respectively. Recoveries ranged from 65 to 97% for the two compounds and intra- and inter-day coefficients of variation were always less than 9%. The limit of quantitation of the method was found to be 5 ng/ml for the two compounds, hence allowing its use for single low dose pharmacokinetics.
authors.affiliation: Département Universitaire de Psychiatrie Adulte, Hôpital de Cery, Prilly-Lausanne, Switzerland.
authors.forename: C B
authors.initials: CB
authors.lastname: Eap
authors.forename: C
authors.initials: C
authors.lastname: Schnyder
authors.forename: L
authors.initials: L
authors.lastname: Savary
mesh_terms: D000081:Acetamides; D002753:Chlorzoxazone / Q000031:analogs & derivatives* / Q000097:blood*; D005463:Fluoroacetates; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D009125:Muscle Relaxants, Central / Q000097:blood*; D017646:Organosilicon Compounds; D012680:Sensitivity and Specificity
chemical_list: D000081:Acetamides; D005463:Fluoroacetates; D009125:Muscle Relaxants, Central; D017646:Organosilicon Compounds; C039289:6-hydroxychlorzoxazone; C059151:N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide; D002753:Chlorzoxazone