A simple and rapid method for the identification of zolpidem carboxylic acid in urine.
Zolpidem is a non-benzodiazepine hypnotic that has been implicated in both drug-facilitated sexual assault and drink spiking. Detection of the drug in urine is extremely difficult because of its extensive metabolism. A method is presented for the detection and quantitation of zolpidem carboxylic acid (ZCA), the major urinary metabolite of zolpidem. The metabolite was extracted from urine at pH 4.5-5.0 with chloroform/isopropanol alkylated with ethyl iodide and identified by gas chromatography-mass spectrometry in the selected ion-monitoring mode. Following a single ingestion of 10 mg zopidem, ZCA is detected for up to 72 h. The limit of detection is 2 ng/mL, with an overall recovery of 80%. Using this procedure, zolpidem was identified in two cases of alleged drug-facilitated sexual assault.
Lewis
John H
JH
Toxicology Unit, Pacific Laboratory Medicine Services, P.O. Box 53, North Ryde, New South Wales 1670, Australia. j.lewis@unsw.edu.au
Vine
John H
JH
D001711:Biotransformation; D005260:Female; D005554:Forensic Medicine / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006993:Hypnotics and Sedatives / Q000493:pharmacokinetics / Q000652:urine*; D011725:Pyridines / Q000493:pharmacokinetics / Q000652:urine*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012742:Sex Offenses; D015813:Substance Abuse Detection / Q000379:methods*; D000077334:Zolpidem
D006993:Hypnotics and Sedatives; D011725:Pyridines; D000077334:Zolpidem; C521325:zolpidem carboxylic acid