Identification of parent benzodiazepines by gas chromotography/mass spectroscopy (GC/MS) from urinary extracts treated with B-glucuronidase.
Urinary glucuronide metabolites of the benzodiazepines were converted back to the parent molecules after treatment with B-glucuronidase. The benzodiazepines were extracted by a one-step liquid/liquid extraction from urine or by a liquid/solid phase extraction. For the limit of detection (LOD), a standard solution of diazepam and oxazepam was serially diluted and analyzed to the point at which a reproducible analytical result was no longer obtained. Using a temperature program and a splitless mode of injection, excellent quantitation was achieved within an 8-min run time. Based upon specimens obtained from patients under a physician's care, we have determined that urinary concentrations of the benzodiazepines > 200 ng/ml are most likely due to abuse rather than to a prescribed ingestion under strict medical surveillance. Therefore, the calibration standard and cutoff concentration for a positive result was set at 200 ng/ml.
Needleman
S B
SB
Navy Drug Screening Laboratory, Great Lakes, IL 60088, USA.
Porvaznik
M
M
D000525:Alprazolam / Q000652:urine; D001569:Benzodiazepines / Q000652:urine*; D002707:Chlordiazepoxide / Q000652:urine; D002998:Clonazepam / Q000652:urine; D003975:Diazepam / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D005966:Glucuronidase; D006801:Humans; D008140:Lorazepam / Q000652:urine; D010076:Oxazepam / Q000652:urine; D014229:Triazolam / Q000652:urine
D001569:Benzodiazepines; D014229:Triazolam; D002998:Clonazepam; D010076:Oxazepam; D002707:Chlordiazepoxide; D005966:Glucuronidase; D008140:Lorazepam; D003975:Diazepam; D000525:Alprazolam