Synthetic cathinones are recreational drugs that mimic the effects of illicit stimulants like cocaine, amphetamine or Ecstasy. Among the available synthetic cathinones in the United States, 3,4-methylenedioxypyrovalerone (MDPV) is commonly abused and associated with dangerous side effects. MDPV is a dopamine transporter blocker 10-fold more potent than cocaine as a locomotor stimulant in rats.
We developed and validated a liquid chromatography–high resolution mass spectrometry method to quantify MDPV and its primary metabolites in 100 mL human and rat plasma. Plasma hydrolysis was followed by protein precipitation before analysis. Limits of detection were 0.1 mg L1, with linear ranges from 0.25 to 1000 mg L1.
As proof of this method, rat plasma specimens were analyzed after intraperitoneal and subcutaneous dosing with MDPV (0.5 mg kg1). MDPV, 3,4-catechol-PV and 4-OH-3-MeO-PV concentrations ranged from not detected to 107.5 mg L1. Read it here.
A sensitive and specific analytical method for cannabidiol (CBD) in urine was needed to define urinary CBD pharmacokinetics after controlled CBD administration, and to confirm compliance with CBD medications including Sativex—a cannabis plant extract containing 1:1 Δ9-tetrahydrocannabinol (THC) and CBD. Non-psychoactive CBD has a wide range of therapeutic applications and may also influence
psychotropic smoked cannabis effects. Few methods exist for the quantification of CBD excretion in urine, and no data are available for phase II metabolism of CBD to CBD-glucuronide or CBD-sulfate. We optimized the hydrolysis of CBD-glucuronide and/or -sulfate, and developed and validated a GC-MS method for urinary CBD quantification. Solid-phase extraction isolated and concentrated analytes prior to GC-MS.
Method validation included overnight hydrolysis (16 h) at 37 °C with 2,500 units of BG100. Enzyme hydrolyzed urine specimens exhibited more than a 250-fold CBD concentration increase compared to alkaline and non-hydrolyzed specimens. This method can be applied for urinary CBD quantification and further pharmacokinetics characterization following controlled CBD administration. Full text here.
Δ9-Tetrahydrocannabinol (THC) is the most commonly analyzed cannabinoid in oral fluid (OF); however, its metabolite 11-nor-9-carboxy-THC (THCCOOH) offers the advantage of documenting active consumption, as it is not detected in cannabis smoke. Analytical
challenges such as low (ng/L) THCCOOH OF concentrations hampered routine OF THCCOOH monitoring. Presence of minor cannabinoids like cannabidiol and cannabinol offer the advantage of identifying recent cannabis intake. Published OF cannabinoids methods have limitations, including few analytes and lengthy derivatization. We developed and validated a sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for THC, its metabolites, 11-hydroxy-THC and THCCOOH quantification, and other natural cannabinoids including tetrahydrocannabivarin (THCV), cannabidiol (CBD), and cannabigerol (CBG) in 1mL OF collected with the Quantisal device.
This method will be highly useful for workplace, criminal justice, drug treatment and driving under the influence of cannabis OF testing. Read the article here.