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

Abstract

A rapid and sensitive method for the simultaneous confirmatory analysis of three forensic most relevant cannabinoids, Delta(9)-tetrahydrocannabinol (THC), 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy-Delta(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 x 2 mm i.d., 3 micro m) 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.

Delta-9-tetrahydrocannabinol (THC) serum concentrations and pharmacological effects in males after smoking a combination of tobacco and cannabis containing up to 69 mg THC

“…The tubes were allowed to clot 0.5-2 h, then they were centrifuged for 10 min at 1,300×g and stored at −20°C until analysis. Serum concentrations of THC, 11-OH-THC and THC-COOH were determined by DeltaLab (The Netherlands) using solid phase extraction and liquid chromatography electrospray tandem mass spectrometry detection (Kintz and Cirimele 1997;Gustafson et al 2003;Maralikova and Weinmann 2004).…”

Confirmatory analysis for drugs of abuse in plasma and urine by high-performance liquid chromatography?tandem mass spectrometry with respect to criteria for compound identification

“…Two millilitres of 0.1 M acetic acid was added into 1 ml of sample and this mixture was vortex-mixed for 20 s. This solution was applied onto preconditioned SPE cartridge for extraction. Detailed SPE program of Zymark RapidTrace SPE-Automat is published elsewhere [17]. The extracts were evaporated to dryness in a speed vacuum concentrator at 40 • C, 500 Pa.…”

Determination of ∆-9-Tetrahydrocannabinol (THC), 11-hydroxy-THC, 11-nor-9-carboxy-THC and Cannabidiol in Human Plasma using Gas Chromatography–Tandem Mass Spectrometry

“…More recently 2-dimensional GC-MS has been employed to provide more sensitive analysis of plasma cannabinoids (31,32). In recent years, several liquid chromatography-tandem mass spectrometric (LC-MS-MS) methods have been described for analysis of plasma cannabinoids (33)(34)(35)(36)(37). Because cannabinoid compounds are very lipophilic, extraction procedures are often complicated.…”