title: Determination of the enantiomers of zopiclone and its two chiral metabolites in urine using an automated coupled achiral-chiral chromatographic system.
abstract: The enantiomers of zopiclone and its two chiral N-desmethyl and N-oxide metabolites were determined in urine using a coupled achiral-chiral liquid chromatographic method. After liquid-liquid extraction, zopiclone and its two metabolites were quantified on a cyanopropyl column. After fluorimetric detection on the achiral system, the eluent was switched through a silica precolumn in order to trap and concentrate the analytes. Each fraction was then backflushed separately onto a carbamate cellulose chiral stationary phase in order to determine the enantiomeric ratios. The coupled system was automated with an autosampler and a switching valve programmed by an integrator. The method was validated, and a first trial was performed on urine samples of a volunteer treated with 15 mg of racemic zopiclone.
authors.affiliation: Hôpital Pitié Salpêtrière, Service Pharmacie, Paris, France.
authors.forename: C
authors.initials: C
authors.lastname: Fernandez
authors.forename: F
authors.initials: F
authors.lastname: Gimenez
authors.forename: B
authors.initials: B
authors.lastname: Baune
authors.forename: V
authors.initials: V
authors.lastname: Maradeix
authors.forename: A
authors.initials: A
authors.lastname: Thuillier
authors.forename: R
authors.initials: R
authors.lastname: Farinotti
mesh_terms: D053961:Azabicyclo Compounds; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D006993:Hypnotics and Sedatives / Q000378:metabolism / Q000652:urine*; D010879:Piperazines / Q000378:metabolism / Q000652:urine*; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013237:Stereoisomerism
chemical_list: D053961:Azabicyclo Compounds; D006993:Hypnotics and Sedatives; D010879:Piperazines; C515050:zopiclone; C053228:zopiclone N-oxide; C053229:N-desmethylzopiclone