Cannabinoid concentrations in confiscated cannabis samples and in whole blood and urine after smoking CBD-rich cannabis as a "tobacco substitute".

In Switzerland, only cannabis with a total Δ9-tetrahydrocannabinol (THC) content higher than 1% is controlled by the narcotics legislation. Cannabis products rich in cannabidiol (CBD) and low in THC can be legally sold as tobacco substitutes. In this paper, we address analytical and forensic toxicological issues related to the increasing availability and consumption of these products. Based on the analysis of 531 confiscated cannabis samples, we could establish classification thresholds: plant material with a ratio of total THC/total CBD ≥ 3 is graded as THC-rich/CBD-poor, whereas samples with a ratio ≤ 0.33 are categorized as CBD-rich/THC-poor cannabis. We also evaluated an on-site test kit as a rapid alternative to the laborious liquid or gas chromatography (LC or GC)-based techniques normally used for the differentiation between THC- and CBD-cannabis. Furthermore, we determined whole blood and urine cannabinoid levels after smoking different doses of legal CBD-cannabis. A male volunteer smoked one cigarette within 15 min and four cigarettes within 1 h and within 30 min, respectively. Cigarettes contained on average 42.7 mg CBD and 2.2 mg THC. Blood samples were collected up to 1.1 h and urine samples up to 27.3 h after the beginning of smoking. All urine samples tested negative by three immunochemical assays for detection of cannabis use. This is an important finding for abstinence monitoring. However, we found that the trace amounts of THC present in CBD-cannabis can produce THC blood levels above the Swiss legal limit for driving, and thus render the consumer unable to drive from a legal point of view.

High-Resolution Ion Mobility Spectrometry for Rapid Cannabis Potency Testing.

We report initial results from an ion mobility spectrometry (IMS)-based analysis of natural cannabis samples and explore the possibility of using this technique to distinguish medical marijuana from illegal forms of the drug, as defined by Swiss legislation. We analyzed cannabis extracts by electrospray ionization IMS-MS and found that high-resolution drift-tube IMS ( R > 150) can effectively isolate and quantify the controlled substance, Δ9-tetrahydrocannabinol (THC), even in the presence of other noncontrolled cannabinoid isomers including cannabidiol (CBD). We used this information to determine whether the THC content of a given sample surpassed the legal limit, which is 1% by weight in Switzerland. Our IMS-MS methodology produced equivalent quantification results to standard HPLC-based methods and offers the additional advantage of significantly shorter time requirements for the analysis. In addition, IMS-based analysis offers flexibility over HPLC in that it can be performed on portable devices. As such, these findings may have implications for cannabis testing in police laboratories.

Accelerated quantification of amphetamine enantiomers in human urine using chiral liquid chromatography and on-line column-switching coupled with tandem mass spectrometry.

Amphetamine (AM) is a powerful psychostimulant existing in two enantiomeric forms. Stereoselective analysis of AM in biosamples can assist clinicians and forensic experts in differentiating between abuse of illicitly synthesized racemic AM and ingestion of pharmaceutical AM formulations containing either S-AM or different proportions of the S- and R-enantiomers. Therefore, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying AM enantiomers in urine was newly developed. The method comprised dilution with water, followed by injection of the diluted sample onto an achiral C18 trapping column for purification and subsequent backflush elution to a chiral Lux 3 µm AMP LC column by means of a switching valve. An isocratic mobile phase of 25 % acetonitrile in 0.1 M aqueous ammonia was used for enantiomeric separation. Injection, cleanup, and backflush of the next sample were performed before the previous sample had eluted from the analytical column, thus enabling simultaneous enantioseparation of up to three samples within the analytical column. This novel chromatographic concept allowed for increased sample throughput by accelerating both the sample preparation and the LC analysis. Analyte detection was accomplished by electrospray ionization in positive ion mode and selected reaction monitoring using a triple-stage quadrupole mass spectrometer. The method was successfully validated through assessment of its linearity, lower limit of quantification, accuracy and precision, selectivity, matrix effect, carry-over, dilution integrity, and re-injection reproducibility. Linearity ranged from 0.05 to 25 mg/L for both enantiomers. Proof of the method included analysis of urine samples obtained from drug abusers and patients receiving an S-AM prodrug. Graphical Abstract Enantioselective determination of amphetamine in human urine using liquid chromatography with achiral-chiral column-switching and tandem mass spectrometry.

Development of a rapid column-switching LC-MS/MS method for the quantification of THCCOOH and THCCOOH-glucuronide in whole blood for assessing cannabis consumption frequency.

The concentration of 11-nor-9-carboxy-Δ(9)-tetrahydrocannabinol (THCCOOH) in whole blood is used as a parameter for assessing the consumption behavior of cannabis consumers. The blood level of THCCOOH-glucuronide might provide additional information about the frequency of cannabis use. To verify this assumption, a column-switching liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the rapid and direct quantification of free and glucuronidated THCCOOH in human whole blood was newly developed. The method comprised protein precipitation, followed by injection of the processed sample onto a trapping column and subsequent gradient elution to an analytical column for separation and detection. The total LC run time was 4.5 min. Detection of the analytes was accomplished by electrospray ionization in positive ion mode and selected reaction monitoring using a triple-stage quadrupole mass spectrometer. The method was fully validated by evaluating the following parameters: linearity, lower limit of quantification, accuracy and imprecision, selectivity, extraction efficiency, matrix effect, carry-over, dilution integrity, analyte stability, and re-injection reproducibility. All acceptance criteria were analyzed and the predefined criteria met. Linearity ranged from 5.0 to 500 µg/L for both analytes. The method was successfully applied to whole blood samples from a large collective of cannabis consumers, demonstrating its applicability in the forensic field.

Quantitative determination of CBD and THC and their acid precursors in confiscated cannabis samples by HPLC-DAD.

Analysis of cannabis has gained new importance worldwide, mainly for quality control within the legalized recreational and medical cannabis industry, but also for forensic differentiation between drug-type cannabis and legal products such as fiber hemp and CBD-rich/THC-poor cannabis. We herein present an HPLC-DAD method for quantitative analysis of major neutral and acidic cannabinoids in herbal cannabis and hashish: Δ9-tetrahydrocannabinol (THC), Δ9-tetrahydrocannabinolic acid A (THCA), cannabidiol (CBD), cannabidiolic acid (CBDA), and cannabinol (CBN). Plant material was dried, homogenized and extracted with a mixture of methanol/hexane. Chromatographic separation of the analytes was achieved on a core-shell C8 column using gradient elution with water/acetonitrile containing 0.1% formic acid. The analytical run time was 13 min and analytes were detected at 210 nm. The method is selective, sensitive, accurate, and precise, as confirmed through validation according to ICH and AOAC guidelines. Linearity in herbal cannabis ranged from 0.04 to 4.00% for the neutral cannabinoids, and from 0.40 to 20% for the acids. Linear ranges in hashish samples were 0.13-13.33% and 1.33-66.66%, respectively. The presented method was successfully applied to characterize 110 cannabis samples seized by the Swiss police, demonstrating its applicability for routine cannabis potency testing in the forensic setting.

A preliminary investigation of lung availability of cannabinoids by smoking marijuana or dabbing BHO and decarboxylation rate of THC- and CBD-acids.

Highly potent cannabis concentrates obtained by butane or by supercritical carbon dioxide-extraction are gaining popularity. These extracts called butane hash oil (BHO) with Δ9-tetrahydrocannabinolic acid A (THCA) contents above 60% are consumed by flash vaporization on a glowing titanium nail, followed by inhalation of the resulting vapor through a water pipe in a single puff - a technique referred to as "dabbing". We herein investigated the decarboxylation rate of THCA during artificial smoking of cannabis plant material and simulated dabbing, and the lung availability of Δ9-tetrahydrocannabinol (THC) which we define as the recovery of THC in the smoke and vapor condensates. Preliminary smoking and dabbing experiments were performed using an apparatus built in-house. Due to availability of cannabidiol (CBD)-rich hemp in Switzerland, we included a sample of CBD flowers in our experiments and investigated the decarboxylation and recovery of cannabidiolic acid (CBDA) and CBD, respectively. Decarboxylation of THCA and CBDA during combustion of the plant material and vaporization of the BHO, respectively, was complete. The high recovery of total THC (75.5%) by dabbing cannot be achieved by smoking marijuana. Lung availability ranged from 12% for mixed cannabis material with a rather low THC content, to approximately 19-27% for marijuana flowers, similar for THC in marijuana as for CBD in CBD-rich marijuana. In reality, when smoking a joint, further losses in recovery must be assumed by additional sidestream smoke. The rather high lung availability of THC via dabbing can explain the increased psychoactive and adverse effects associated with this new trend of cannabis consumption.

Study of the in vitro and in vivo metabolism of the tryptamine 5-MeO-MiPT using human liver microsomes and real case samples.

The synthetic tryptamine 5-methoxy-N-methyl-N-isopropyltryptamine (5-MeO-MiPT) has recently been abused as a hallucinogenic drug in Germany and Switzerland. This study presents a case of 5-MeO-MiPT intoxication and the structural elucidation of metabolites in pooled human liver microsomes (pHLM), blood, and urine. Microsomal incubation experiments were performed using pHLM to detect and identify in vitro metabolites. In August 2016, the police encountered a naked man, agitated and with aggressive behavior on the street. Blood and urine samples were taken at the hospital and his premises were searched. The obtained blood and urine samples were analyzed for in vivo metabolites of 5-MeO-MiPT using liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS). The confiscated pills and powder samples were qualitatively analyzed using Fourier transform infrared (FTIR), gas chromatography-mass spectrometry (GC-MS), LC-HRMS/MS, and nuclear magnetic resonance (NMR). 5-MeO-MiPT was identified in 2 of the seized powder samples. General unknown screening detected cocaine, cocaethylene, methylphenidate, ritalinic acid, and 5-MeO-MiPT in urine. Seven different in vitro phase I metabolites of 5-MeO-MiPT were identified. In the forensic case samples, 4 phase I metabolites could be identified in blood and 7 in urine. The 5 most abundant metabolites were formed by demethylation and hydroxylation of the parent compound. 5-MeO-MiPT concentrations in the blood and urine sample were found to be 160 ng/mL and 3380 ng/mL, respectively. Based on the results of this study we recommend metabolites 5-methoxy-N-isopropyltryptamine (5-MeO-NiPT), 5-hydroxy-N-methyl-N-isopropyltryptamine (5-OH-MiPT), 5-methoxy-N-methyl-N-isopropyltryptamine-N-oxide (5-MeO-MiPT-N-oxide), and hydroxy-5-methoxy-N-methyl-N-isopropyltryptamine (OH-5-MeO-MiPT) as biomarkers for the development of new methods for the detection of 5-MeO-MiPT consumption, as they have been present in both blood and urine samples.

Rapid quantification of free and glucuronidated THCCOOH in urine using coated well plates and LC-MS/MS analysis.

AIM: Generally, urine drug testing for cannabis abuse involves measuring total concentrations of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCCOOH) obtained by enzymatic and/or alkaline hydrolysis of THCCOOH-glucuronide. As hydrolysis can be inconsistent and incomplete, direct measurement of the two metabolites is preferable. Methodology & results: We developed a high-throughput LC-MS/MS method for simultaneous quantification of free and glucuronidated THCCOOH in urine using coated 96-well plates for analyte extraction and column-switching chromatography. Excellent separation of the two analytes was achieved within 2.5 min, with linear ranges from 5 to 2000 µg/l for THCCOOH and from 10 to 4000 µg/l for THCCOOH-glucuronide. CONCLUSION: The method was successfully validated and applied to authentic urine samples from cannabis consumers, demonstrating its applicability for routine cannabinoid testing.

Assessing cannabis consumption frequency: Is the combined use of free and glucuronidated THCCOOH blood levels of diagnostic utility?

Heavy cannabis consumption is considered incompatible with safe driving. In Swiss traffic policy, drivers suspected of regular cannabis use are therefore required to undergo medical assessment of their long-term fitness to drive. A whole blood concentration of the cannabis metabolite 11-nor-9-carboxy-Δ9 -tetrahydrocannabinol (THCCOOH) of 40 µg/L is currently used by Swiss forensic experts as the decision limit for regular cannabis consumption. The present study aimed to investigate the suitability of THCCOOH-glucuronide blood levels as an additional and/or better marker for the frequency of cannabis use. Whole blood samples collected from 23 heavy (≥10 joints/month) and 25 occasional smokers (≥1 joint/month, but ≤ 1 joint/week) enrolled in a placebo-controlled cannabis smoking study were analyzed for THCCOOH and THCCOOH-glucuronide. Based on receiver operating characteristic (ROC) curve analysis, concentration thresholds could be established for distinguishing between these two groups. Proposed thresholds for heavy use were THCCOOH-glucuronide > 52 µg/L (100% specificity; 41% sensitivity) and/or total THCCOOH > 58 µg/L (100% specificity; 43% sensitivity). Optimum thresholds for occasional use were THCCOOH-glucuronide < 5 µg/L (73% specificity; 97% sensitivity) and/or total THCCOOH < 5 µg/L (62% specificity; 98% sensitivity). Our results indicate that the THCCOOH-glucuronide whole blood concentration is a useful parameter that complements the free THCCOOH level to assess the frequency of cannabis consumption. The consideration of the blood concentrations of both free and glucuronidated THCCOOH improves the identification of heavy users whose fitness to drive has to be carefully assessed. Copyright © 2016 John Wiley & Sons, Ltd.

Interactions of Polyvinylpyrrolidone with Chlorin e6-Based Photosensitizers Studied by NMR and Electronic Absorption Spectroscopy.

Polyvinylpyrrolidone (PVP) can act as potential drug delivery vehicle for porphyrin-based photosensitizers in photodynamic therapy (PDT) to enhance their stability and prevent porphyrin self-association. In the present study the interactions of PVP (MW 10 kDa) were probed with five different derivatives of chlorin e6 (CE6) bearing either one of the amino acids serine, lysine, tyrosine or arginine, or monoamino-hexanoic acid as substituent. All derivatives of CE6 (xCE) formed aggregates of a similar structure in aqueous buffer in the millimolar range. In the presence of PVP monomerization of all xCE aggregates could be proved by (1)H NMR spectroscopy. xCE-PVP complex formation was confirmed by (1)H NMR T2 relaxation and diffusion ordered spectroscopy (DOSY). (1)H(1)H-NOESY data suggested that the xCE uptake into the PVP polymer matrix is governed by hydrophobic interactions. UV-vis absorption and fluorescence emission bands of xCE in the micromolar range revealed characteristic PVP-induced bathochromic shifts. The presented data point out the potential of PVP as carrier system for amphiphilic derivatives of chlorin e6. The capacity of PVP to monomerize xCE aggregates may enhance their efficiency as possible photosensitizers in PDT.