Determination of 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid in urine using high-performance liquid chromatography and electrospray ionization mass spectrometry

Automation System for the Flexible Sample Preparation for Quantification of Δ9-THC-D3, THC-OH and THC-COOH from Serum, Saliva and Urine

In the life sciences, automation solutions are primarily established in the field of drug discovery. However, there is also an increasing need for automated solutions in the field of medical diagnostics, e.g., for the determination of vitamins, medication or drug abuse. While the actual metrological determination is highly automated today, the necessary sample preparation processes are still mainly carried out manually. In the laboratory, flexible solutions are required that can be used to determine different target substances in different matrices. A suitable system based on an automated liquid handler was implemented. It has been tested and validated for the determination of three cannabinoid metabolites in blood, urine and saliva. To extract Δ9-tetrahydrocannabinol-D3 (Δ9-THC-D3), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC-COOH) from serum, urine and saliva both rapidly and cost-effectively, three sample preparation methods automated with a liquid handling robot are presented in this article, the basic framework of which is an identical SPE method so that they can be quickly exchanged against each other when the matrix is changed. If necessary, the three matrices could also be prepared in parallel. For the sensitive detection of analytes, protein precipitation is used when preparing serum before SPE and basic hydrolysis is used for urine to cleave the glucuronide conjugate. Recoveries of developed methods are >77%. Coefficients of variation are <4%. LODs are below 1 ng/mL and a comparison with the manual process shows a significant cost reduction.

Determination of Enzymatic Hydrolysis Efficiency in Detection of Cannabis Use by UPLC-MS/MS

Cannabis is still the most widely used illegal plant in the world. However, cannabis use is prohibited in many countries. After cannabis use, Δ9-tetrahydrocannabinol is metabolized in the liver to 11-nor-9-carboxy-Δ9- tetrahydrocannabinol (THC-COOH) and most undergo glucuronidation. THC-COOH and THC-COOH glucuronide are excreted in the urine. The total concentration of THC-COOH in the urine sample is measured to determine cannabis use. The total concentration is determined after enzymatic or alkaline hydrolysis. In this study, comparing enzymatic hydrolysis efficiency is presented comprehensively together with the method developed for the determination of total 11-nor-9-carboxy-Δ9-tetrahydrocannabinol in the urine. Also, the method was validated according to the European Medicines Agency (EMA) Guideline on bioanalytical method validation. The method has rapid hydrolysis time (20 min), rapid analysis time (5 min), and simple sample preparation. The lower limit of quantitation of the developed method was 1 ng/mL for 11-nor-9-carboxy-Δ9- tetrahydrocannabinol. The calibration curve of 11-nor-9-carboxy-Δ9- tetrahydrocannabinol was between 1-2000 ng/mL with a correlation coefficient>0.99. Also, the method was applied to real patient's urine. We think that the results will provide a new perspective on enzymatic hydrolysis optimization studies.

Characteristics of opioid-maintained clients smoking fentanyl patches: The importance of confirmatory drug analysis illustrated by a case series and mini-review

The increase in opioid prescribing in many European countries over the last decade has raised concerns about associated diversion, overdose, and mortality. Fentanyl is one of these synthetic opioids that is typically prescribed as a transdermal patch for pain that requires continuous pain relief and has been the focus of investigation due to reports of overdose and death. We report a case series of 14 drug addiction treatment entrants, who entered treatment in a service located in the region of Southern Denmark from August 2015 to December 2015 for smoking fentanyl patches. Clients presented with difficulties breathing and pains in the lungs. The clients had a history of past opioid use, including heroin. Relapses resulted in treatment disengagement. Immunoassays for fentanyl were used in the service. In some cases, false negative results occurred. Clients' urine samples were subsequently analysed in a collaborating laboratory. Seven clients tested positive for fentanyl. One client was positive for both fentanyl and heroin. Analyses were also positive for other opioids and metabolites in 6 clients, predominantly codeine and oxycodone. Results from confirmatory analysis contributed to clearer insights into clients' drug histories, which facilitated personalised care plans consisting of opioid agonist therapy informed by confirmed drug use. In Denmark, prescription levels of fentanyl are high, which has been accompanied by observations of diversion and smoking in a smaller population. In addition to revision of inappropriate prescribing to reduce diversion, we recommend increased reliance upon confirmatory drug analysis in the addiction treatment sector in Denmark.

Simultaneous determination of major phytocannabinoids, their main metabolites, and common synthetic cannabinoids in urine samples by LC-MS/MS

Simultaneous determination of major phytocannabinoids (THC, CBD, CBN), their main metabolites (11-OH-THC, THC-COOH, THC-COOH-glucuronide) and common synthetic cannabinoids (HU-210, JWH-018, JWH-073, JWH-250) remains an issue in forensic toxicology. The present study has developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously detect the above 10 analytes in human urine samples. The chromatographic separation was performed on an ACQUITY UPLC(®)BEH Phenyl 1.7μm (2.1×100mm) column, using a mobile phase consisting of 0.1% formic acid in water and acetonitrile at a flow rate of 0.3mL/min in gradient elution mode. The limit of detection (LOD) and limit of quantification (LOQ) of all analytes were 0.01-0.5ng/mL and 0.05-1ng/mL, respectively. The assay was linear from LOQ to 100ng/mL for phytocannabinoids, their main metabolites and HU-210, and from 0.05 to 50ng/mL for JWH-250, JWH-018 and JWH-073. The extraction recoveries were over 50% and the matrix effects were between 59.4% and 100.1%. The accuracy and precision were <10.4% of bias and <10.5% of relative standard deviation (RSD), respectively. The developed method was applied to 5 urine samples from real caseworks, and the results that THC metabolites together with synthetic cannabinoids were detected demonstrated the effectiveness of our method.

Synthesis of [13C4]-labeled ∆9-tetrahydrocannabinol and 11-nor-9-carboxy-∆9-tetrahydrocannabinol as internal standards for reducing ion suppressing/alteration effects in LC/MS-MS quantification

(-)-∆9-Tetrahydrocannabinol is the principal psychoactive component of the cannabis plant and also the active ingredient in some prescribed drugs. To detect and control misuse and monitor administration in clinical settings, reference samples of the native drugs and their metabolites are needed. The accuracy of liquid chromatography/mass spectrometric quantification of drugs in biological samples depends among others on ion suppressing/alteration effects. Especially, 13C-labeled drug analogues are useful for minimzing such interferences. Thus, to provide internal standards for more accurate quantification and for identification purpose, synthesis of [13C4]-∆9-tetrahydro-cannabinol and [13C4]-11-nor-9-carboxy-∆9-tetrahydrocannabinol was developed via [13C4]-olivetol. Starting from [13C4]-olivetol the synthesis of [13C4]-11-nor-9-carboxy-∆9-tetrahydrocannabinol was shortened from three to two steps by employing nitromethane as a co-solvent in condensation with (+)-apoverbenone.

Simultaneous and sensitive LC-MS/MS determination of tetrahydrocannabinol and metabolites in human plasma

Cannabis is not only a widely used illicit drug but also a substance which can be used in pharmacological therapy because of its analgesic, antiemetic, and antispasmodic properties. A very rapid and sensitive method for determination of ∆(9)-tetrahydrocannabinol (THC), the principal active component of cannabis, and two of its phase I metabolites in plasma has been developed and validated. After solid-phase extraction of plasma (0.2 mL), the clean extracts were analyzed by tandem mass spectrometry after a 5-min liquid chromatographic separation. The linear calibration ranges were from 0.05 to 30 ng mL(-1) for THC and 11-nor-∆(9)-carboxy-tetrahydrocannabinol (THC-COOH) and from 0.2 to 30 ng mL(-1) for ∆(9)-(11-OH)-tetrahydrocannabinol (11-OH-THC). Imprecision and inaccuracy were always below 7 and 12 % (expressed as relative standard deviation and relative error), respectively. The method has been successfully applied to determination of the three analytes in plasma obtained from healthy volunteers after oral administration of 20 mg dronabinol.

Direct quantification of 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid in urine by liquid chromatography/tandem mass spectrometry in relation to doping control analysis

An accurate and precise method for the quantification of 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THCA) in urine by liquid chromatography/tandem mass spectrometry (LC/MS/MS) for doping analysis purposes has been developed. The method involves the use of only 200 microL of urine and the use of D(9)-THCA as internal standard. No extraction procedure is used. The urine samples are hydrolysed using sodium hydroxide and diluted with a mixture of methanol/glacial acetic acid (1:1). Chromatographic separation is achieved using a C8 column with gradient elution. All MS and MS/MS parameters were optimised in both positive and negative electrospray ionisation modes. For the identification and the quantification of THCA three product ions are monitored in both ionisation modes. The method is linear over the studied range (5-40 ng/mL), with satisfactory intra-and inter-assay precision, and the relative standard deviations (RSDs) are lower than 15%. Good accuracy is achieved with bias less than 10% at all levels tested. No significant matrix effects are observed. The selectivity and specificity are satisfactory, and no interferences are detected. The LC/MS/MS method was applied for the analysis of 48 real urine samples previously analysed with a routine gas chromatography/mass spectrometry (GC/MS) method. A good correlation between the two methods was obtained (r(2) > 0.98) with a slope close to 1.

Simultaneous liquid chromatography-mass spectrometry quantification of urinary opiates, cocaine, and metabolites in opiate-dependent pregnant women in methadone-maintenance treatment

Opiates, cocaine, and metabolites were quantified by liquid chromatography-mass spectrometry (LC-MS) in 284 urine specimens, collected thrice weekly, to monitor possible drug relapse in 15 pregnant heroin-dependent women. Opiates were detected in 149 urine specimens (52%) with limits of quantification (LOQ) of 10-50 microg/L. Morphine, morphine-3-glucuronide, and/or morphine-6-glucuronide were positive in 121 specimens; 6-acetylmorphine, a biomarker of heroin ingestion, was quantifiable in only 7. No heroin, 6-acetylcodeine, papaverine, or noscapine were detected. One hundred and sixty-five urine specimens (58%) from all 15 participants were positive for one or more cocaine analytes (LOQ 10-100 microg/L). Ecgonine methylester (EME) and/or benzoylecgonine were the major cocaine biomarkers in 142. Anhydroecgonine methylester, a biomarker of smoked cocaine, was positive in six; cocaethylene and/or ecgonine ethylester, biomarkers of cocaine and ethanol co-ingestion, were found in 25. At the current Substance Abuse Mental Health Services Administration cutoffs for total morphine (2000 microg/L), codeine (2000 microg/L), 6-acetylmorphine (10 microg/L), and benzoylecgonine (100 microg/L), 16 opiate- and 29 cocaine-positive specimens were identified. Considering 100 microg/L EME as an additional urinary cocaine biomarker would identify 51 more positive cocaine specimens. Of interest is the differential pattern of opiate and cocaine biomarkers observed after LC-MS as compared to gas chromatography-mass spectrometry analysis.

Development of a LC/MS/MS method for the analysis of cannabinoids in human EDTA-plasma and urine after small doses of Cannabis sativa extracts

A novel high-performance liquid chromatographic separation method with tandem-mass spectrometry detection was developed for the simultaneous determination of Delta(9)-tetrahydrocannabinol (THC) and its major metabolites 11-hydroxy-Delta(9)-tetrahydrocannabinol (11-OH-THC) and 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) as well as the components cannabidiol (CBD) and cannabinol (CBN) in human EDTA-plasma and urine. Run time was 25 min. Lower limit of quantification was 0.2 ng/ml. The coefficients of variation of all inter- and intra-assay determinations were between 1.3 and 15.5%. The method was successfully applied to the determination of cannabinoids in human plasma and human urine after administration of Delta(9)-tetrahydrocannabinol or Cannabis sativa extracts.

LC–MS method for the estimation of Δ8-THC and 11-nor-Δ8-THC-9-COOH in plasma

The aim of the present study was to develop a simple and sensitive LC-MS method for the estimation of delta8-tetrahydrocannabinol (delta8-THC) and its metabolite, 11-nor-delta8-tetrahydrocannabinol-9-carboxylic acid (11-nor-delta8-THC-9-COOH), in guinea pig plasma after topical drug application. The plasma samples were analyzed by LC-MS using negative-mode electrospray ionization detection and a simple liquid-liquid extraction technique. The mean recoveries for delta8-THC and its metabolite, 11-nor-delta8-THC-9-COOH, were 96.6 and 88.2%, respectively. The lower limits of quantification (LLOQ) for delta8-THC and 11-nor-delta8-THC-9-COOH were 3.97 and 7.26 nM, respectively. The topical treatment steady-state plasma concentrations of delta8-THC and 11-nor-delta8-THC-9-COOH were 8.24-27.63 and 19.66-23.17 nM, respectively, with a lag period of 0.3-2.2 h. This assay method is selective, sensitive, and reproducible for the determination of delta8-THC and 11-nor-delta8-THC-9-COOH at low concentrations in small volumes of plasma.

Novel solid-phase extraction protocol for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol from urine samples employing a polymeric mixed-mode cation-exchange resin, Strata-X-C, suitable for gas chromatography–mass spectrometry or liquid chromatography–mass spectrometry analysis

A novel solid-phase extraction (SPE) method was developed for extraction and cleanup of 11-nor-9-carboxy-delta9-tetrahydrocannabinol (THC-COOH), the major metabolite of the active principle of marijuana, delta9-tetrahydrocannabinol, from urine samples. The protocol utilizes a polymeric mixed-mode cationic sorbent, Strata-X-C, which exhibits strong retention for the metabolite facilitating a more rigorous organic wash to eliminate matrix components/endogenous materials. Acetonitrile containing acetic acid was used as the elution solvent and is compatible with both LC-MS and GC-MS modes of analysis. The hydrophobic retention of Strata-X-C was demonstrated to be higher than a neutral polymeric sorbent, Strata-X, of the same backbone but devoid of the cation-exchange moiety (sulfonic acid), by LC studies employing homologous paraben probes. Simultaneously, the polar (non-ionic) interaction capability of Strata-X-C is also greater than that of Strata-X, as assessed through regioisomeric nitrophenol probes. These two features enable the metabolite to be retained strongly on Strata-X-C. Good linearity and precision was obtained for THC-COOH by GC-MS analysis of its trimethylsilyl derivative in the range 1-50 ng. A simplified room temperature instantaneous derivatization procedure was developed that is suitable for high-throughput screening of THC-COOH.

Liquid chromatographic–mass spectrometric quantitation of Δ9-tetrahydrocannabinol and two metabolites in pharmacokinetic study plasma samples

A sensitive method for the determination of Delta(9)-tetrahydrocannabinol and its metabolites, 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid and 11-hydroxy-Delta(9)-tetrahydrocannabinol, in rat and guinea pig plasma was developed using high-performance liquid chromatographic separation with electrospray ionization mass spectrometry detection and a simple liquid-liquid extraction technique. The mean recoveries for Delta(9)-tetrahydrocannabinol, 11-nor-Delta(9)-tetrahydrocannabinol-9-carboxylic acid, and 11-hydroxy-Delta(9)-tetrahydrocannabinol were 96, 92, and 85%, respectively. The lower limit of quantification (LLOQ) for all three compounds was 5 ng/ml and the limit of detection (LOD) was 2 ng/ml. This assay method utilizes the increased sensitivity and selectivity of mass spectrometric (MS) detection and a simple extraction step for the determination of Delta(9)-tetrahydrocannabinol and its metabolites in plasma, and thus yields a more efficient pharmacokinetic analysis method than has previously been described.

Urine drug testing for opioids, cocaine, and metabolites by direct injection liquid chromatography/tandem mass spectrometry

A sensitive and specific liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the simultaneous quantification of opioids, cocaine, and metabolites in urine was developed and validated. A 10-microL aliquot of urine was injected directly onto the LC/MS/MS system. The lack of sample preparation substantially reduced total analysis time. Separation was performed by reversed-phase chromatography with gradient elution for all analytes in 26 min. Atmospheric pressure chemical ionization (APCI) was a rugged and efficient ionization technique for basic drugs. Identification and quantification was based on selected reaction monitoring (SRM). Calibration, with deuterated internal standards, was performed by linear regression analysis (weighting factor 1/x). Limits of quantitation (LOQ) were established between 10-100 ng/mL and linearity was obtained up to a maximum of 10 000 ng/mL with an average correlation coefficient (R(2)) > 0.99. Analytical validation criteria for specificity, precision, accuracy, dilution integrity, matrix effect, and stability were fulfilled. The method proved to be simple and time efficient, and was applicable for illicit drug use monitoring and methadone treatment compliance in clinical research projects at the National Institute on Drug Abuse (NIDA).

Progress of liquid chromatography-mass spectrometry in clinical and forensic toxicology

The use of liquid chromatography-mass spectrometry (LC-MS) has recently exploded in various analytic fields, including toxicology and therapeutic drug monitoring (although still far behind pharmacokinetics). There is no doubt that LC-MS is currently competing with gas chromatography (GC)-MS for the status of the reference analytic technique in toxicology. This review presents, for the nonspecialist reader, the principles, advantages, and drawbacks of LC-MS systems using atmospheric pressure interfaces. It also gives an overview of the analytic methods for xenobiotics that could be set up with these instruments for clinical or forensic toxicology. In particular, as far as quantitative techniques are concerned, this review tries to underline the large number and variety of drugs or classes of drugs (drugs of abuse, therapeutic drugs) or toxic compounds (e.g., pesticides) that can be readily determined using such instruments, the respective merits of the different ionization sources, and the improvements brought about by tandem MS. It also discusses new applications of LC-MS in the field of toxicology, such as "general unknown" screening procedures and mass spectral libraries using LC-atmospheric pressure ionization (API)-MS or MS-MS, presenting the different solutions proposed to overcome the naturally low fragmentation power of API sources. Finally, the opportunities afforded by the most recent or proposed instrument designs are addressed.

Liquid chromatography-mass spectrometry in the study of the metabolism of drugs and other xenobiotics

The application of liquid chromatography-mass spectrometry (LC/MS) to the study of metabolism of drugs and other xenobiotics is reviewed. Original research papers covering the period from 1998 to early 2000 and concerning the use of LC/MS in the study of xenobiotic metabolism in humans and other mammalian species are reviewed. LC/MS interfaces, sample preparation steps, column types, mobile phases and additives, and the type of metabolites detected are summarized and discussed in an attempt to identify the current and future trends in the use of LC/MS for metabolism studies. Applications are listed according to the parent xenobiotic type and include substances used in therapeutics, drug candidates, compounds being evaluated in clinical trials, environmental pollutants, adulterants and naturally occurring substances.

Liquid chromatography-mass spectrometry in forensic toxicology

Liquid chromatography-mass spectrometry has evolved from a topic of mainly research interest into a routinely usable tool in various application fields. With the advent of new ionization approaches, especially atmospheric pressure, the technique has established itself firmly in many areas of research. Although many applications prove that LC-MS is a valuable complementary analytical tool to GC-MS and has the potential to largely extend the application field of mass spectrometry to hitherto "MS-phobic" molecules, we must recognize that the use of LC-MS in forensic toxicology remains relatively rare. This rarity is all the more surprising because forensic toxicologists find themselves often confronted with the daunting task of actually searching for evidence materials on a scientific basis without any indication of the direction in which to search. Through the years, mass spectrometry, mainly in the GC-MS form, has gained a leading role in the way such quandaries are tackled. The advent of robust, bioanalytically compatible combinations of liquid chromatographic separation with mass spectrometric detection really opens new perspectives in terms of mass spectrometric identification of difficult molecules (e.g., polar metabolites) or biopolymers with toxicological relevance, high throughput, and versatility. Of course, analytical toxicologists are generally mass spectrometry users rather than mass spectrometrists, and this difference certainly explains the slow start of LC-MS in this field. Nevertheless, some valuable applications have been published, and it seems that the introduction of the more universal atmospheric pressure ionization interfaces really has boosted interests. This review presents an overview of what has been realized in forensic toxicological LC-MS. After a short introduction into LC-MS interfacing operational characteristics (or limitations), it covers applications that range from illicit drugs to often abused prescription medicines and some natural poisons. As such, we hope it can act as an appetizer to those involved in forensic toxicology but still hesitating to invest in LC-MS.

Validation of urine drug-of-abuse testing methods for ketobemidone using thin-layer chromatography and liquid chromatography-electrospray mass spectrometry

High-performance thin-layer chromatography (TLC) with visual detection (post-chromatographic derivatization) was used in screening for the drug ketobemidone in human urine samples. High-performance liquid chromatography with electrospray mass spectrometry (LC-ESI-MS) was used for final confirmation of the result. The clean-up was performed by mixed-mode solid-phase extraction, and nalorphine was used as internal standard. A screening cut-off for TLC was established at 0.2 microg/ml. The mean recovery for LC-MS was 91% (n=60) with coefficients of variation (C.V.) in the range of 7 to 16%. Qualifying fragment ions of ketobemidone (m/z 190, 201 and 230) were generated by up front collision-induced dissociation (CID) on a single quadrupole instrument. Relative ion intensities were within +/- 15% deviation compared with standards in the same batch. The limit of detection for LC-MS was 0.025 microg/ml. Positive clinical samples from drug abusers (n=10) had concentrations in the range 0.07 to 3.2 microg/ml, which could be determined by LC-MS without matrix interference. During screening of unknown clinical samples (n=27) the results from TLC was in agreement with LC-MS data. After acid hydrolysis of conjugates in clinical samples the analyte response of ketobemidone and norketobemidone was increased by a factor of approximately two and twelve, respectively. A qualitative GC-MS technique was demonstrated for the detection of the spasmolyticum A29 (N,N-dimethyl-4,4-diphenyl-3-buten-2-amine), which can be found in a preparation combined with ketobemidone (Ketogan).