title: Flunitrazepam excretion patterns using the Abuscreen OnTrak and OnLine immunoassays: comparison with GC-MS.
abstract: A study was conducted to compare the performance of the OnLine and OnTrak immunoassays for benzodiazepines with gas chromatographic-mass spectrometric (GC-MS) analysis in detecting flunitrazepam (FNP) and its metabolites in human urine. Urine was collected over a 72-h period from six individuals (four male and two female) who had taken a single oral dose of either 1 or 4 mg of FNP. The OnTrak assay was run at a 100-ng/mL cutoff of nordiazepam (NDP), and the OnLine assay was run with a standard curve from zero to 200 ng/mL of NDP with and without beta-glucuronidase treatment. Each sample was analyzed by GC-MS using FNP, 7-amino-FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP as standards with beta-glucuronidase treatment. The specimens from the 1-mg dose did not yield a positive result by immunoassay over the 72-h collection period. Specimens from the 4-mg dose did yield positive results in both immunoassays. The time of the first positive result ranged from 4 to 12 h, and the time to the last positive result ranged from 18 to 60 h. Treatment of the samples with beta-glucuronidase increased the OnLine values between 20 and 60%, but it did not appreciably increase the detection time. GC-MS analysis showed no detectable levels of FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP. However, all samples collected past time zero showed detectable levels of 7-amino-FNP (> 2 ng/mL) with peak concentrations at 12-36 h. The peak levels of 7-amino-FNP by GC-MS paralleled the peak levels of the immunoassay response. The amount of 7-amino-FNP metabolite quantitated by GC-MS, however, accounted for only 15-20% of the total immunoassay crossreactive FNP metabolites.
authors.affiliation: Roche Diagnostic Systems, Somerville, New Jersey 08876, USA.
authors.forename: S J
authors.initials: SJ
authors.lastname: Salamone
authors.forename: S
authors.initials: S
authors.lastname: Honasoge
authors.forename: C
authors.initials: C
authors.lastname: Brenner
authors.forename: A J
authors.initials: AJ
authors.lastname: McNally
authors.forename: J
authors.initials: J
authors.lastname: Passarelli
authors.forename: K
authors.initials: K
authors.lastname: Goc-Szkutnicka
authors.forename: R
authors.initials: R
authors.lastname: Brenneisen
authors.forename: M A
authors.initials: MA
authors.lastname: elSohly
authors.forename: S
authors.initials: S
authors.lastname: Feng
mesh_terms: D000284:Administration, Oral; D000328:Adult; D014151:Anti-Anxiety Agents / Q000008:administration & dosage / Q000652:urine*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005445:Flunitrazepam / Q000008:administration & dosage / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009862:Online Systems
chemical_list: D014151:Anti-Anxiety Agents; D005445:Flunitrazepam