| |
Published:
Journal of Analytical Toxicology,
ISSN 0146-4760,
Volume 32, Number 7, September,
pp.499-504
Chiral Analysis
of Methadone and its Main Metabolite EDDP in Postmortem Blood by
Liquid Chromatography–Mass Spectrometry
Sys Stybe Johansen and Kristian Linnet
Section of Forensic Chemistry, Department of Forensic Medicine,
Faculty of Health Sciences, University of Copenhagen, Copenhagen,
Denmark
A chiral liquid chromatography–tandem mass
spectrometry method was developed for the measurement of methadone
and 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium (EDDP) enantiomers
in postmortem blood. Blood (0.100 g) was mixed with water and
aqueous methadone-d3 and EDDP-d3 solutions.
After addition of NaOH, extraction was carried out with butyl
acetate. Chromatographic separation was performed on a chiral-AGP
analytical column (100 mm × 4.0-mm i.d., 5 µm) with
a mobile phase of acetonitrile/ammonium acetate buffer (10 mM,
pH 7.0, 22:78, v/v). A Quattro micro mass spectrometer was operated
in the positive ion mode with an electrospray source. Multiple
reaction monitoring was used with two transitions for each compound.
The calibration curves were linear over the range from 0.001
to 2.5 mg/kg blood per enantiomer, and the limit of detection
was 0.001 mg/kg, and the limit of quantitation was 0.003 mg/kg
for all compounds. The precision (coefficient of variation%)
was below 6.3%, and the trueness was 88–104%
for all compounds. R- and S-methadone were
measured in femoral blood from 10 postmortem cases. The R-methadone
concentrations extended from 0.006 to 1.235 mg/kg with a median
of 0.41 mg/kg, and the S-methadone concentrations ranged
from 0 to 0.794 mg/kg (median 0.33 mg/kg). The median R/S-ratio
was 1.46 (total range from 1.00 to 2.62), which tends to be higher
than that reported in plasma of living subjects.
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
| |
