Determination of the Cross-Reactivity of the Biological Metabolite (-)-trans-Δ9-Tetrahydrocannabinol-Carboxylic Acid-Glucuronide (THC-COOH-Gluc) for Cannabinoid Immunoassays

Analytical techniques for screening of cannabis and derivatives from human hair specimens

Cannabis and associated substances are some of the most frequently abused drugs across the globe, mainly due to their anxiolytic and euphorigenic properties. Nowadays, the analysis of hair samples has been given high importance in forensic and analytical sciences and in clinical studies because they are associated with a low risk of infection, do not require complicated storage conditions, and offer a broad window of non-invasive detection. Analysis of hair samples is very easy compared to the analysis of blood, urine, and saliva samples. This review places particular emphasis on methodologies of analyzing hair samples containing cannabis, with a special focus on the preparation of samples for analysis, which involves screening and extraction techniques, followed by confirmatory assays. Through this manuscript, we have presented an overview of the available literature on the screening of cannabis using mass spectroscopy techniques. We have presented a detailed overview of the advantages and disadvantages of this technique, to establish it as a suitable method for the analysis of cannabis from hair samples.

The cross-reactivity of cannabinoid analogs (delta-8-THC, delta-10-THC and CBD), their metabolites and chiral carboxy HHC metabolites in urine of six commercially available homogeneous immunoassays

There has been an exponential surge in the presence and use of cannabinoids since the federal legalization of hemp (Agricultural Improvement Act of 2018). This growth is attributed to delta-9-tetrahydrocannabinol (delta-9-THC) and cannabidiol (CBD), the most abundant phytocannabinoid components of cannabis and hemp, respectively, but with many other emerging THC analogs. Structurally, these analogs are similar to delta-9-THC, yet very little information is available about their potency and even less information is available regarding their detectability using commercially available cannabinoid screening kits. Due to their structural similarity, current cannabinoid homogeneous immunoassay screening methods may be able to detect these emerging cannabinoid analogs and their metabolites. Six urine immunoassay kits (Abbott Cannabinoids-Abbott Diagnostics, LZI Cannabinoids (cTHC) Enzyme Immunoassay-Lin-Zhi International, DRI® Cannabinoid Assay and CEDIA™ THC-Thermo Fisher Scientific, ONLINE DAT Cannabinoid II-Roche Diagnostics and Syva EMIT®II Plus-Siemens Healthineers) were evaluated at two different cutoff concentrations: 50 ng/mL and 20 or 25 ng/mL, assay dependent. The analysis was performed on an Abbott Architect Plus c4000 (Abbott Diagnostics). Delta-8-THC, CBD, olivetol and their major metabolites, and delta-10-THC and HHC carboxylic acid chiral analogs were evaluated. The cross-reactivity was evaluated by preparing each analyte at 20, 50, 100 and 1,000 ng/mL in urine. Analytes that did not cross-react at 1,000 ng/mL for a cutoff were considered not detectable. If detected, the lowest concentration was used as the decision point to determine the precision at the immunoassay's cutoff. The six commercially available urine cannabinoid homogeneous immunoassay screening kits cross reacted with the following analogs: delta-8-THC, 11-OH-delta-8-THC, 11-COOH-delta-8-THC, 6-OH-CBD, 7-OH-CBD, all delta-10-THC and HHC carboxylic acid chiral analogs and olivetol with varying selectivity depending on the screening kit and cutoff concentration. The kits did not cross-react with the following analogs: CBD, 7-COOH-CBD, Abnormal CBD, CBDA-A and olivetolic acid.

Development of a quick preparation method for the analysis of 11-nor-9-carboxy-∆9-tetrahydrocannabinol in human urine by phenylboronic-acid solid-phase extraction

A rapid preparation method for the analysis of the urine from a cannabis user was established. Generally, 11-nor-9-carboxy-∆9-tetrahydrocannabinol (THC-COOH), which is one of the main metabolites of ∆9-tetrahydorocannabinol (THC), must be detected from a user's urine to verify cannabis use. However, existing preparation methods are usually multistep and time-consuming processes. Before the analysis by liquid-chromatography tandem mass spectrometry (LC-MS/MS), deconjugation by treatment with β-glucuronidase or alkaline solution, liquid-liquid extraction or solid-phase extraction (SPE), and evaporation are generally performed. In addition, subsequent derivatization (silylation or methylation) are certainly necessary for gas-chromatography mass spectrometry (GC/MS) analysis. Here, we focused on the phenylboronic-acid (PBA) SPE, which selectively binds compounds with a cis-diol moiety. THC-COOH is metabolized as a glucuronide conjugate (THC-COOGlu) which has cis-diol moieties, therefore, we investigated the conditions of its retention and elution to reduce the operating time. We developed four elution conditions, which afford the following derivatives: acidic elution for THC-COOGlu, alkaline elution for THC-COOH, methanolysis elution for the THC-COOH methyl ester (THC-COOMe), and methanolysis elution and following methyl etherification for O-methyl-THC-COOMe (O-Me-THC-COOMe). All repeatability and recovery rates were evaluated by LC-MS/MS in this study. As a result, these four pathways required short times (within 10-25 min) and exhibited good repeatability and recovery rates. Detection limits of pathway I-IV were 10.8, 1.7, 18.9, and 13.8 ng mL-1, respectively. Lower limits of quantification were 62.5, 31.25, 57.3, and 62.5 ng mL-1, respectively. When proof of cannabis use is required, any elution condition can be selected to match the possessing reference standards and analytical instruments. To our knowledge, this is the first report of using PBA SPE for the preparation of the urine samples containing cannabis and achieving partial derivatization when eluting from a PBA carrier. Our method can provide a new and practical solution for the preparation of the urine samples from cannabis users. Although the PBA SPE method cannot recover THC-COOH in urine because of its lack of a 1,2-diol moiety, this method has technological advantages for simplifying the process and reducing the operating time, thereby avoiding human errors.

Δ9-cis-Tetrahydrocannabinol: Natural Occurrence, Chirality, and Pharmacology

The cis-stereoisomers of Δ⁹-THC [(-)-3 and (+)-3] were identified and quantified in a series of low-THC-containing varieties of Cannabis sativa registered in Europe as fiber hemp and in research accessions of cannabis. While Δ⁹-cis-THC (3) occurs in cannabis fiber hemp in the concentration range of (-)-Δ⁹-trans-THC [(-)-1], it was undetectable in a sample of high-THC-containing medicinal cannabis. Natural Δ⁹-cis-THC (3) is scalemic (ca. 80-90% enantiomeric purity), and the absolute configuration of the major enantiomer was established as 6aS,10aR [(-)-3] by chiral chromatographic comparison with a sample available by asymmetric synthesis. The major enantiomer, (-)-Δ⁹-cis-THC [(-)-3], was characterized as a partial cannabinoid agonist in vitro and elicited a full tetrad response in mice at 50 mg/kg doses. The current legal discrimination between narcotic and non-narcotic cannabis varieties centers on the contents of "Δ⁹-THC and isomers" and needs therefore revision, or at least a more specific wording, to account for the presence of Δ⁹-cis-THCs [(+)-3 and (-)-3] in cannabis fiber hemp varieties.