Identification of the synthetic cannabinoid <Emphasis Type="Italic">N</Emphasis>-(2-phenyl-propan-2-yl)-1-(4-cyanobutyl)-1<Emphasis Type="Italic">H</Emphasis>-indazole-3-carboxamide (CUMYL-4CN-BINACA) in a herbal mixture product

We were the first to detect N-(2-phenylpropan-2-yl)-1-(4-cyanobutyl)-1H-indazole-3-carboxamide (common name CUMYL-4CN-BINACA) as a new synthetic cannabinoid, on the illegal market in Bursa, Turkey. To elucidate the chemical structure, the dried herbal mixture was extracted with methanol. The extract was purified by column chromatography. Pure compound was analyzed by gas chromatography–mass spectrometry (GC–MS), attenuated total reflection Fourier-transform infrared spectroscopy (FT-IR), and one- and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. The GC–MS, FT-IR and ¹H and ¹³C NMR spectra of the compound coincided well with the reference data. All protons and carbons were assigned by their couplings and correlations observed in ¹H-¹H correlation spectroscopy, ¹H-¹³C heteronuclear multiple bond correlation, and ¹H-¹³C heteronuclear single quantum coherence spectra. On the basis of the spectral data, the compound was identified as CUMYL-4CN-BINACA. Herewith, we report analytical characteristics of CUMYL-4CN-BINACA enabling its (and possible analogues thereof) determination in criminal seizures.     

Spectroscopic and crystallographic characterization of two cathinone derivatives: 1-(4-fluorophenyl)-2-(methylamino)pentan-1-one (4-FPD) hydrochloride and 1-(4-methylphenyl)-2-(ethylamino)pentan-1-one (4-MEAP) hydrochloride

Purpose

In this study, we performed identification and physicochemical characterization of two cathinone derivatives, 4-FPD and 4-MEAP, found in market-available materials.

Methods

The compounds were characterized by electrospray ionization ion trap mass spectrometry (MS) in MS² and MS³ modes, gas chromatography–MS, infrared, Raman and ultraviolet-visible spectroscopies, X-ray crystallography, differential scanning calorimetry and nuclear magnetic resonance spectroscopy.

Results

We could obtain detailed and comprehensive physicochemical characterization of 4-FPD and 4-MEAP—new cathinone derivatives available on the designer drugs market.

Conclusions

Dynamic growth in the number of psychoactive substances available on the designer drug markets makes it compulsory to obtain analytical data allowing unequivocal identification of these drugs in the fastest possible way. In this study we presented analytical data useful in quick identification of the investigated compounds.

     

Spectroscopic characterization and crystal structures of two cathinone derivatives: 1-(4-chlorophenyl)-2-(1-pyrrolidinyl)-pentan-1-one (4-chloro-α-PVP) sulfate and 1-(4-methylphenyl)-2-(dimethylamino)-propan-1-one (4-MDMC) hydrochloride salts,seized on illicit drug market

Purpose

Two compounds newly found in the seizures by drug enforcement agencies were identified and characterized by various instrumental analytical methods.

Methods

The obtained powder samples were analyzed by gas chromatography–mass spectrometry (GC–MS), liquid chromatography–mass spectrometryⁿ (LC–MSⁿ), nuclear magnetic resonance (NMR) spectroscopy, infrared and Raman spectroscopy and X-ray crystallography.

Results

The two compounds were tentatively identified as 4-chloro-α-PVP and 4-MDMC by GC–MS, and LC–MS/MS. The confirmation of the results was made by NMR spectroscopy. The X-ray crystallography gave information that 4-chloro-α-PVP and 4-MDMC were in salted forms with sulfate and hydrochloride, respectively; in addition, both compounds existed as racemic mixtures.

Conclusions

We could identify 4-chloro-α-PVP and 4-MDMC in the seizure powder samples by various analytical methods. X-ray crystallography was especially useful for identifying the salted forms and enantiomeric forms.

     

In vitro and in vivo metabolisms of 1-pentyl-3-(4-methyl-1-naphthoyl)indole (JWH-122)

1-Pentyl-3-(4-methyl-1-naphthoyl)indole (JWH-122) is an agonist of the cannabinoid receptors CB₁ and CB₂. In this study, the phase I and phase II metabolisms of JWH-122 were investigated using two models. In vitro studies using incubations of JWH-122 with human liver microsomes were performed to obtain metabolites of the drug at the initial step; 11 classes of metabolites were found and analyzed by liquid chromatography–mass spectrometry (LC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS). Hydroxylation(s) on the naphthalene moiety and/or the indole moiety of the molecule took place as such or in combination with dehydrogenation or cleavage of the N-pentyl side chain. Furthermore, dihydrodiol metabolites were formed probably via epoxide formation on the naphthalene moiety, irrespective of the combination with hydroxylation(s). A metabolite carrying a carboxyl group on the N-pentyl side chain was also detected. As the second step of the study, in vivo experiments using chimeric mice were performed; the mice were orally administered JWH-122, and their urine samples were collected, subjected to enzymatic hydrolysis, and analyzed by LC–MS and LC–MS–MS. The urine samples without hydrolysis were also analyzed for their molecular formulae in the conjugated forms by LC–high resolution MS. The in vivo model using chimeric mice confirmed most metabolite classes and clarified the phase II metabolism of JWH-122. It was concluded that all metabolites formed in vivo were excreted conjugated as glucuronide or sulfate, with conjugation rates above 50 %.     

Identification and quantitation of JWH-213, a cannabimimetic indole, as a designer drug in a herbal product

In our survey of designer drugs in the Japanese market, a cannabimimetic indole was identified as a new active compound in a herbal product. The structure of this compound was elucidated by liquid chromatography–photodiode array–mass spectrometry (LC–PDA–MS), gas chromatography–mass spectrometry (GC–MS), high-resolution MS, and nuclear magnetic resonance (NMR) analyses. The compound was finally identified as (4-ethyl-1-naphthalenyl)(2-methyl-1-pentyl-1H-indol-3-yl)methanone (JWH-213), an indole-based cannabinoid receptor ligand. To our knowledge, this is the first finding of JWH-213 as a designer drug in a herbal product. The quantitative LC–PDA analysis showed that the JWH-213 content in the product was 252 mg/pack.     

Reporting the novel synthetic cathinone 5-PPDI through its analytical characterization by mass spectrometry and nuclear magnetic resonance

Purpose

In this work, the identification and characterization of the novel synthetic cathinone 5-PPDI found in a suspect drug sample were performed.

Methods

The suspect sample was analyzed by gas chromatography–mass spectrometry (GC–MS), Fourier-transformed infrared (FTIR) spectroscopy, ultra-high performance liquid chromatography–high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy.

Results

The fragmentation observed in GC–MS and the identification of functional groups by FTIR was not enough for compound identification. After an exhaustive analysis of the accurate-mass fragmentation observed in HRMS, the compound was tentatively identified as the novel cathinone 5-PPDI. Finally, five different NMR experiments were used for the unequivocal identification and complete characterization of the compound. In addition, the origin of this cathinone was investigated in depth.

Conclusions

The analytical data provided in this work will be useful for the identification of 5-PPDI by forensic laboratories. In addition, the origin of this cathinone has been investigated, which could be of interest for the identification of future synthetic cathinones prepared following the similar synthesis route.

     

Simultaneous determination of tryptamine analogues in designer drugs using gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry

In recent years, a large number of tryptamine-based designer drugs have been encountered in forensic samples. We have developed simultaneous analytical methods for 14 tryptamine analogues using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS). Trimethylsilyl (TMS) derivatives of the analytes were separated on a DB-1ms column within 15 min. The structural isomers could be differentiated by electron ionization GC–MS. LC–MS–MS with a C₁₈ column could separate structural isomers of tryptamines except for a combination of 5-methoxy-N,N-diethyltryptamine and 5-methoxy-N-methyl-N-isopropyltryptamine. Higher collision energy gave different product ion spectra between the structural isomers. The results indicate that GC–MS is the first choice for identification of tryptamines, preferably after TMS derivatization, and LC–MS–MS can be used as a complementary approach for the unequivocal differentiation of tryptamine isomers.     

Identification of (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone and its 5-pentyl fluorinated analog in herbal incense seized for drug trafficking

Four herbal incense products were seized from suspected drug abusers in Korea. The major ingredients in the herbal incense samples were purified, and their structures were elucidated using gas chromatography–electron ionization–mass spectrometry (GC–EI–MS), liquid chromatography–time-of-flight–mass spectrometry (LC–TOF–MS), and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. As a result, ingredients in the herbal incense were identified as (1-pentylindol-3-yl)-(2,2,3,3-tetramethylcyclopropyl)methanone and its 5-pentyl fluorinated analog [1-(5-fluoropentyl)indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone. The former is being sold via the Internet as a "research chemical" named UR-144, and the latter is sold as 5F-UR-144. UR-144 is a selective full agonist of CB₂ cannabinoid receptor, and was first developed by Abbott Laboratories as an analgesic. It exhibits analgesic activity against both neuropathic and inflammatory pain associated mainly with the CB₂ receptor, but shows less psychotropic effects associated with the CB₁ receptor. Fluorination of the N-pentyl side chain of cannabimimetic compounds increases their cannabinoid receptor affinity such as with AM-2201, which shows both increased analgesic and psychotropic effects simultaneously. UR-144 and 5F-UR-144 can be classified as research chemicals based on their analgesic effects, but in practice are abused as psychotropic agents and can cause unexpected toxic effects. Thus, the trade and diversion of these chemicals should be monitored carefully for possible abuse. To our knowledge, this is the first report disclosing cyclopropylcarbonylindoles in herbal products.     

Identification of a new synthetic cannabinoid in a herbal mixture: 1-butyl-3-(2-methoxybenzoyl)indole

Two unknown cannabimimetic compounds were detected in a seized herbal mixture after gas chromatography–mass spectrometry (GC–MS) screening. To elucidate the chemical structures, 0.3 g of the dried plant material was extracted with methanol and concentrated under reduced pressure. The extract was purified by silica gel column chromatography with methylene chloride and methanol. Pure compounds were isolated by preparative high-performance liquid chromatography (HPLC) and then analyzed by electrospray ionization (ESI) mass spectrometry (MS) with direct flow injection, high-resolution ESI-time-of-flight (TOF)–MS and one-dimensional and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. GC–MS spectra showed that the base ion at m/z 321 for compound 1 was the same as that of 1-pentyl-3-(4-methoxybenzoyl)indole (RCS-4), and the fragment ions were almost the same as those of RCS-4. The GC–MS spectrum of compound 2 was very similar to that of compound 1 except that the mass numbers of the fragment ions at m/z 290, 200, 186, and 173 of compound 2 were equally smaller than those of compound 1 by 14 amu. From these GC–MS results, compound 1 was assumed to be the 2- or 3-methoxy isomer of RCS-4, and compound 2 was assumed to be a 1-butylindole homologue of compound 1. The ESI mass spectra showed a single peak at m/z 322.33 for compound 1 and a single peak at m/z 308.25 for compound 2, which showed the masses of the protonated ions. High-resolution TOF–MS spectra showed the accurate mass numbers of protonated molecular ions at m/z 322.180512 for compound 1 and at m/z 308.164895 for compound 2, suggesting the molecular formulas of C₂₁H₂₃NO₂ and C₂₀H₂₁NO₂, respectively. The ¹H NMR spectra showed signals that suggested 23 and 21 protons for compounds 1 and 2, respectively, while the respective ¹³C NMR spectra showed 21 and 20 carbon signals. All protons and carbons were assigned by their couplings and correlations observed in ¹H–¹H correlation spectroscopy (COSY), ¹H–¹³C heteronuclear multiple bond correlation (HMBC), and ¹H–¹³C heteronuclear single quantum coherence (HSQC) spectra. On the basis of the spectral data, compound 1 was identified as the 2-methoxy isomer of RCS-4; compound 2 was identified for the first time as 1-butyl-3-(2-methoxybenzoyl)indole. Phenazepam and 5-methoxy-N,N-diallyltryptamine (5-MeO-DALT) were also identified as coexisting drugs in the herbal mixture. The contents of compounds 1 and 2 in the mixture were calculated to be 22.4 and 3.45 mg/g, respectively.     

Quantification of clitidine in caps and stems of poisonous mushroom Paralepistopsis acromelalga by hydrophilic interaction liquid chromatography–tandem mass spectrometry

Purpose

A simple and high-throughput analytical method for determining clitidine in Paralepistopsis acromelalga using hydrophilic interaction liquid chromatography–tandem mass spectrometry (LC–MS/MS) was established.

Methods

To determine clitidine in the mushrooms, a simple procedure including dilution with methanol solution and filtering by cartridge was employed just before quantification by LC–MS/MS for high-throughput analysis. In this report, concentrations of clitidine in mushrooms were determined by the standard addition method.

Results

The present established method was successfully applied to the analysis of fruit bodies of P. acromelalga, which were obtained from five different locations in Japan. Results on concentrations of clitidine in each stem and cap of P. acromelalga specimens tested showed that their concentrations were quite different, not only between stems and caps, but also among locations and strains; the concentrations of clitidine in stems and caps ranged from 1.41 to 9.30 mg/g and 3.17 to 14.4 mg/g, respectively.

Conclusions

This is the first report to present a detailed quantitative analysis of clitidine by MS and the distribution of clitidine in stems and caps of P. acromelalga. This analytical method for clitidine was thought to be useful in P. acromelalga poisoning cases to identify the causative toxic mushroom.

     

Characterization of the designer benzodiazepine pyrazolam and its detectability in human serum and urine

In 2012, online shops selling so-called research chemicals started offering pyrazolam, a new benzodiazepine that differs from phenazepam and etizolam, which have also recently appeared on the “gray market”, in that it is not marketed by pharmaceutical companies anywhere in the world. This article describes the characterization of pyrazolam (8-bromo-1-methyl-6-pyridin-2-yl-4H-[1,2,4]triazolo[4,3–a][1, 4]benzodiazepine) using gas chromatography-mass spectrometry, liquid chromatography-tandem mass spectrometry (LC–MS–MS), liquid chromatography quadrupole time-of-flight mass spectrometry (LC–Q–TOF–MS), and nuclear magnetic resonance spectroscopy. In addition, a study was carried out in which one of the authors ingested two 0.5-mg pyrazolam tablets. Serum and urine samples were then obtained to investigate the metabolism of pyrazolam and to obtain preliminary results for the elimination half-life and the detectability of a 1-mg dose in serum and urine using a highly sensitive LC–MS–MS method and immunoassays. The results showed an elimination half-life of about 17 h and no detectable metabolism. The parent compound was detected with the described LC–MS–MS method in serum for more than 50 h and in urine for approximately 6 days. Immunoassays showed cross-reactivity, but poor detection in the study samples demonstrated that consumption or administration of this presumably potent drug could go undetected unless instrumental analytical techniques are also used.     

Two new synthetic cannabinoids, AM-2201 benzimidazole analog (FUBIMINA) and (4-methylpiperazin-1-yl)(1-pentyl-1H-indol-3-yl)methanone (MEPIRAPIM), and three phenethylamine derivatives, 25H-NBOMe 3,4,5-trimethoxybenzyl analog, 25B-NBOMe, and 2C-N-NBOMe, identified in illegal products

Two new types of synthetic cannabinoids, an AM-2201 benzimidazole analog (FUBIMINA, 1) and (4-methylpiperazin-1-yl)(1-pentyl-1H-indol-3-yl)methanone (MEPIRAPIM, 2), and three newly emerged phenethylamine derivatives, 25B-NBOMe (3), 2C-N-NBOMe (4), and a 25H-NBOMe 3,4,5-trimethoxybenzyl analog (5), were detected in illegal products distributed in Japan. The identification was based on liquid chromatography–mass spectrometry (LC–MS) and gas chromatography–mass spectrometry (GC–MS), high-resolution MS, and nuclear magnetic resonance analyses. Different from the representative synthetic cannabinoids, such as JWH-018, which have a naphthoylindole moiety, compounds 1 and 2 were completely new types of synthetic cannabinoids; compound 1 had a benzimidazole group in place of an indole group, and compound 2 had a 4-methylpiperazine group in place of the naphthyl group. Compounds 3 and 4 were N-o-methoxybenzyl derivatives of 2,5-dimethoxyphenethylamines (25-NBOMe series), which had been previously detected in European countries, but have newly emerged in Japan. Compound 5 had an N-trimethoxybenzyl group in place of an N-o-methoxybenzyl group. Data on the chemistry and pharmacology of compounds 1, 2, and 5 have never been reported to our knowledge.     

A novel method to distinguish β-methylphenylethylamines from isomeric α-methylphenylethylamines by liquid chromatography coupled to electrospray ionization mass spectrometry

Purpose

Various phenylethylamines have been detected lately in dietary or sports supplements. N-Methyl-2-phenylpropan-1-amine (phenpromethamine) and 2-phenylpropan-1-amine (β-methylphenylethylamine, BMPEA) are known to produce mass spectra almost identical to those produced by methamphetamine (MA) and amphetamine (AP), respectively, when analyzed by liquid chromatography/mass spectrometry (LC/MS). They may interfere with the analysis of MA and AP. The aims of the present study were to determine whether some substances other than phenpromethamine and BMPEA give mass spectra similar to those given by MA or AP and to develop an analytical method of distinguishing phenpromethamine from MA and BMPEA from AP by derivatization.

Methods

Twenty isomers of MA or AP were selected to be analyzed using LC/MS. Six reagents were examined for derivatization of MA, AP, phenpromethamine, and BMPEA. Three mass spectrometers from two manufacturers were evaluated for their ability to reproduce the data.

Results

All isomers except phenpromethamine and BMPEA were shown to be distinguishable from MA and AP by their mass spectra. For the discrimination of isomeric pairs, derivatization using N-succinimidyl-4-nitrophenylacetate was found to be the best for tandem mass spectrometry and that using 4-nitrobenzoyl chloride was the best for in-source collision-induced dissociation. One or more ions from each pair of isomers gave adequate difference in their relative intensities according to the World Anti-Doping Agency criteria.

Conclusions

The newly developed method was proved to be usable for discriminating among those phenylethylamines.

     

Identification of two new-type synthetic cannabinoids, N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA), and detection of five synthetic cannabinoids, AM-1220, AM-2233, AM-1241, CB-13 (CRA-13), and AM-1248, as designer drugs in illegal products

Two new-type synthetic cannabinoids, N-(1-adamantyl)-1-pentyl-1H-indole-3-carboxamide (APICA, 1) and N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (APINACA, 2), have been identified as designer drugs in illegal products being sold in Japan. The identification was based on liquid chromatography-mass spectrometry (LC-MS), gas chromatography-mass spectrometry (GC-MS), high-resolution MS and nuclear magnetic resonance (NMR) analyses. Both mass and NMR spectrometric data revealed that 1 was 1-pentyl-N-tricyclo[3.3.1.1^3,7]dec-1-yl-1H-indole-3-carboxamide, and 2 was 1-pentyl-N-tricyclo[3.3.3.1.^3,7]dec-1-yl)-1H-indazole-3-carboxamide. Although many of the synthetic cannabinoids detected in illegal products, such as JWH-018, have a 3-carbonyl indole moiety, compounds 1 and 2 are a new type of synthetic cannabinoid having an amide and an adamantyl group, and 2 also has an indazole group in place of an indole group. There has been no synthetic, chemical, or biological information about 1 or 2 until now, making this the first report of these cannabimimetic compounds (1 and 2) as designer drugs. In addition, five synthetic cannabinoids, AM-1220, AM-2233, AM-1241, CB-13 (CRA-13), and AM-1248, are also described herein as newly distributed designer drugs in Japan.     

[1-(Tetrahydropyran-4-ylmethyl)-1H-indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone: a new synthetic cannabinoid identified on the drug market

A new synthetic cannabinoid, [1-(tetrahydropyran-4-ylmethyl)-1H-indol-3-yl]-(2,2,3,3-tetramethylcyclopropyl)methanone, was identified in several resinous samples seized by law enforcement officers in Poland. Its identification was based on liquid chromatography–electrospray ionization–quadrupole time-of-flight–mass spectrometry, gas chromatography–electron ionization–mass spectrometry, one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy, and Fourier-transform infrared spectroscopy. The reported substance was first developed by Abbott Laboratories and patented under the name “A-834,735”. It is a potent agonist of both CB₁ and CB₂ receptors. Although A-834,735 shows moderate selectivity to CB₂ receptor, it exhibits a CB₁ affinity similar to that of ?⁹-tetrahydrocannabinol. The drug has recently become available in online shops. To our knowledge, this is the first report to disclose a synthetic cannabinoid containing a (tetrahydropyran-4-yl)methyl structure in products seized from the drug market.     

A GC–MS method for the determination of furanylfentanyl and ocfentanil in whole blood with full validation

Purpose

Fentanyl analogues are popular in recent years among drug addicts and have been related to many overdoses and deaths worldwide. Furanylfentanyl, ocfentanil, acetylfentanyl and butyrfentanyl are among the most common of these drugs. Methods for the determination of furanylfentanyl and ocfentanil by gas chromatography–mass spectrometry (GC–MS) in biological samples do not exist, and therefore, their development would be extremely useful for routine toxicological analysis.

Methods

A GC–MS method was developed and fully validated for the determination of furanylfentanyl and ocfentanil in whole blood. This method was also suitable for the determination of acetylfentanyl and butyrfentanyl. The method included solid-phase extraction after protein precipitation using acetonitrile, and it was applied during the toxicological investigation of forensic cases. Methadone-d₃ was used as internal standard for the quantification of the analytes.

Results

The limit of detection and limit of quantification values were 0.30 and 1.0 ng/mL for furanylfentanyl and ocfentanil and 0.15 and 0.50 ng/mL for acetylfentanyl and butyrfentanyl, respectively. The calibration curves were linear (R²?≥?0.993) from 1.00 to 100 ng/mL for furanylfentanyl and ocfentanil and from 0.50 to 50.0 ng/mL for acetylfentanyl and butyrfentanyl. The recoveries were not lower than 85%, while accuracies and precisions were not greater than 6.0% (% error) and 8.0% (% relative standard deviation), respectively, for all four fentanyl analogues.

Conclusions

The developed method is the first one in the literature for the detection of furanylfentanyl and ocfentanil in biological fluids by GC–MS, and it provides very high sensitivity comparable to that by liquid chromatography–tandem mass spectrometry.

     

Differentiation of regioisomeric fluoroamphetamine analogs by gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry

In recent years, a large number of clandestinely produced controlled-substance analogs (designer drugs) of amphetamine with high structural variety have been detected in forensic samples. Analytical differentiation of regioisomers is a significant issue in forensic drug analysis because, in most cases, legal controls are placed only on one or two of the three isomers. In this study, we used gas chromatography–mass spectrometry (GC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) for the differentiation of regioisomers of fluoroamphetamine analogs (fluoroamphetamines and fluoromethamphetamines), which were synthesized in our laboratories. Free bases and their acylated and silylated derivatives were subjected to GC–MS analysis using DB-1ms, DB-5ms, and DB-17ms capillary columns. The separation of free bases was incomplete on all columns. Trifluoroacetyl derivatives of 3- and 4-positional isomers showed slight separation on DB-1ms and DB-5ms. On the other hand, trimethylsilyl derivatization enabled baseline separation of six fluoroamphetamine analogs on DB-1ms and DB-5ms columns, which was sufficient for unequivocal identification. For LC–MS/MS, a pentafluorophenyl column was able to separate six regioisomeric fluoroamphetamine analogs but a conventional C18 column could not achieve separation between 3- and 4-positional isomers. These results show that a suitable choice of derivatization and analytical columns allows the differentiation of regioisomeric fluoroamphetamine analogs.     

Supramolecular solvent (SUPRASs) extraction method for detecting benzodiazepines and zolpidem in human urine and blood using gas chromatography tandem mass spectrometry

ObjectiveA high-throughput and sensitive method using supramolecular solvent (SUPRASs) for detecting 9 benzodiazepines and zolpidem in human urine and blood by gas chromatography-tandem mass spectrometry (GC–MS/MS) was newly established and applied to authentic human urine and blood samples in this study.MethodsUrine and blood samples were subjected to liquid–liquid extractions with supramolecular solvent mixture which consists of tetrahydrofuran and 1-hexanol. The solvent layer was evaporated to dryness by stream of nitrogen. The residue was reconstituted with methanol, and subjected to analysis by GC–MS/MS in multiple reaction monitoring (MRM) mode; internal standard method was employed for quantifying of each targeted compound.ResultsThe regression equation has a good linear relationship with correlation coefficients for all tested compounds were not lower than 0.9991. The lower limits of the quantification ranged from 0.20 to 5 ng/mL for tested compounds in urine; Meanwhile, the lower limits of the quantification in this method ranged from 1 to 50 ng/mL for tested compounds in blood. These results showed that excellent reproducibility and satisfactory extraction recovery rates could be obtained for the established analytical method for 10 drugs in both blood and urine samples.ConclusionThe established method in this study was high-throughput, simple and sufficiently sensitive for determining of benzodiazepinesand zolpidem in human urine and blood. Therefore, this newly established method could be of use for qualitative and quantitative determination of such drugs in urine and blood samples either for clinical poisoning monitoring or for forensic identification.