title: Chromatographic screening for zopiclone and metabolites in urine using liquid chromatography and liquid chromatography-mass spectrometry techniques.
abstract: Zopiclone is a benzodiazepine-like hypnotic that was believed not to have any abuse potential. Nevertheless, during the past few years there have been an increasing number of reports on the abuse and misuse of zopiclone. Despite this, methods for screening analysis in urine are lacking. To investigate whether UV detection would be possible to use for this purpose, a liquid chromatography method with ultraviolet detection for analyzing zopiclone and its urinary metabolites was developed, with liquid chromatography-mass spectrometry for confirmation. The method was used for analyzing samples from subjects receiving methadone. The limits of detection were approximately 100 ng/mL in control urine samples and 500 ng/mL in urine samples from subjects receiving methadone. However, due to the high background in these patients' urine, a single therapeutic dose was impossible to detect.
authors.affiliation: Institution of Medicine, Department of Clinical Pharmacology, L7:05, Karolinska Institutet, S-171 76 Stockholm, Sweden. Helena.Nordgren@ks.se
authors.forename: Helena K
authors.initials: HK
authors.lastname: Nordgren
authors.forename: Karl
authors.initials: K
authors.lastname: Bodin
authors.forename: Olof
authors.initials: O
authors.lastname: Beck
mesh_terms: D000328:Adult; D053961:Azabicyclo Compounds; D002853:Chromatography, Liquid; D005260:Female; D006801:Humans; D006993:Hypnotics and Sedatives / Q000493:pharmacokinetics* / Q000652:urine; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000493:pharmacokinetics* / Q000652:urine; D013048:Specimen Handling; D013056:Spectrophotometry, Ultraviolet; D015813:Substance Abuse Detection / Q000379:methods / Q000592:standards*
chemical_list: D053961:Azabicyclo Compounds; D006993:Hypnotics and Sedatives; D010879:Piperazines; C515050:zopiclone