Simultaneous determination of Δ9-tetrahydrocannabinol, 11-hydroxy-Δ9-tetrahydrocannabinol and 11-nor-9-carboxy- Δ9-tetrahydrocannabinol in human plasma by high-performance liquid chromatography/tandem mass spectrometry

✍ Scribed by Barbora Maralikova; Wolfgang Weinmann

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: English
• Weight: 143 KB
• Volume: 39
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.616

✦ Synopsis

Abstract

A rapid and sensitive method for the simultaneous confirmatory analysis of three forensic most relevant cannabinoids, Δ^9^‐tetrahydrocannabinol (THC), 11‐hydroxy‐Δ^9^‐tetrahydrocannabinol (11‐OH‐THC) and 11‐nor‐9‐carboxy‐Δ^9^‐tetrahydrocannabinol (THC‐COOH), by means of high‐performance liquid chromatography/tandem mass spectrometry (LC/MS/MS) in human plasma was developed and fully validated. Sample clean‐up was performed by automated silica‐based solid‐phase extraction and the separation was carried out using a PhenylHexyl column (50 × 2 mm i.d., 3 µm) and acetonitrile–5 mM ammonium acetate gradient elution. Data were acquired with an API 3000 LC/MS/MS system equipped with a turboionspray interface and triple quadrupole mass analyzer using positive electrospray ionization and multiple reaction monitoring. Two MS/MS transitions for each substance were monitored and deuterated analogues of analytes were used as internal standards for quantitation. The limit of quantitation was 0.8 ng ml^−1^ for THC, 0.8 ng ml^−1^ for 11‐OH‐THC and 4.3 ng ml^−1^ for THC‐COOH and linearity with a correlation coefficient r^2^ = 0.999 was achieved up to 100 ng ml^−1^ for THC and 11‐OH‐THC and 500 ng ml^−1^ for THC‐COOH. The limits of detection were 0.2 ng ml^−1^ for THC, 0.2 ng ml^−1^ for 11‐OH‐THC and 1.6 ng ml^−1^ for THC‐COOH. The developed LC/MS/MS method was also successfully used for the determination of THC‐COOH‐glucuronide, the phase II metabolite of THC‐COOH. Copyright © 2004 John Wiley & Sons, Ltd.