| |
Published:
Journal of Analytical Toxicology,
ISSN 0146-4760,
Volume 31, Number 8, October,
pp.477-485
Simultaneous GC–EI-MS Determination
of D9-Tetrahydrocannabinol, 11-Hydroxy-D9-Tetrahydrocannabinol,
and 11-nor-9-Carboxy- D9-Tetrahydrocannabinol in Human Urine
Following Tandem Enzyme-Alkaline Hydrolysis
Tsadik T. Abraham[1], Ross H. Lowe[1],
Stephane O. Pirnay[1,2], William D. Darwin[1], and Marilyn A.
Huestis[1],
[1]Chemistry and Drug Metabolism, Intramural Research Program,
National Institute on Drug Abuse, National Institutes of Health,
5500 Nathan Shock Drive, Baltimore, Maryland, 21224 and
[2]Université Paris
Descartes, Faculté de Pharmacie, Neuropsychopharmacologie
des Addictions, CNRS, UMR7157 et Université Paris 7, INSERM,
U705, Paris F-75010, France
A sensitive and specific method for extraction
and quantification of Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol
(11-OH-THC), and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol
(THCCOOH) in human urine was developed and fully validated. To
ensure complete hydrolysis of conjugates and capture of total
analyte content, urine samples were hydrolyzed by two methods
in series. Initial hydrolysis was with Escherichia coli β-glucuronidase
(Type IX–A) followed by a second hydrolysis utilizing 10N
NaOH. Specimens were adjusted to pH 5–6.5, treated with
acetonitrile to precipitate protein, and centrifuged, and the
supernatants were subjected to solid-phase extraction. Extracted
analytes were derivatized with BSTFA and quantified by gas chromatography–mass
spectrometry with electron impact ionization. Standard curves
were linear from 2.5 to 300 ng/mL. Extraction efficiencies were
57.0–59.3% for THC, 68.3–75.5% for 11-OH-THC, and
71.5–79.7% for THCCOOH. Intra- and interassay precision
across the linear range of the assay ranged from 0.1 to 4.3%
and 2.6 to 7.4%, respectively. Accuracy was within 15% of target
concentrations. This method was applied to the analysis of urine
specimens collected from individuals participating in controlled
administration cannabis studies, and it may be a useful analytical
procedure for determining recency of cannabis use in forensic
toxicology applications.
Reproduction
of editorial content of this journal is prohibited without publisher’s
permission.
This
article is available in its entirety by fax for $40.00 each.
Visa, MasterCard and AMEX accepted.
To
order electronically click here
or call: 847-647-2900 ext. 1323
or fax request to: 847-647-1155.
To order multiple copies click here.
Please indicate JAT
volume and issue along with page numbers. |
|
Home | Subscribe
| Current Issue | Back Issues
| Search | Advertise | Other Publications
| |
