Sara Odoardi

An analytical approach to the forensic identification of different classes of new psychoactive substances (NPSs) in seized materials

RATIONALE New psychoactive substances (NPSs) are rapidly spreading worldwide, and forensic laboratories are often requested to identify new substances for which no reference standards or analytical data are available. This article describes an analytical approach that was adopted in Italy by a few collaborative centres of the Italian Early Warning System for Drugs, which has contributed many alerts for the identification of different classes of NPSs in the last 24 months. METHODS Seized crystals and powders were initially analysed via single quadrupole gas chromatography/mass spectrometry (GC/MS), followed by liquid chromatography/high-resolution mass spectrometry (LC/HRMS) in the positive electrospray ionisation (ESI) mode at 100,000 full width at half maximum resolution (FWHM) without fragmentation to elucidate the elemental compositions of unknown molecules. Different fragmentation voltages during LC/HRMS were applied to study the accurate masses of the obtained characteristic fragments. Nuclear magnetic resonance (NMR) analyses were performed to identify specific isomers when necessary. RESULTS Some interesting examples of unknown NPSs from seizures later identified in our laboratories are reported, with special focus on those cases where analytical standards were not available during analyses. These cases include cathinones, such as 3-methylmethcathinone (3-MMC), methylone, bk-MBDB (butylone), 4-methylethcathinone (4-MEC), flephedrone, methylenedioxypyrovalerone (MDPV) and pentedrone, methoxetamine, apinaca or AKB48, benzydamine, meta-chlorophenylpiperazine (m-CPP), 5-MeO-N,N-dialkyl tryptamines, such as 5-MeO-DALT and 5-MeOMIPT, benzofurans, such as 6-APB and 4-APB, and diphenidine (identified for the first time in Europe). CONCLUSIONS The identification of NPSs in confiscated materials was successfully achieved via GC/MS coupled with LC/HRMS and, in a few cases, NMR analyses. The availability of GC/MS libraries is of great assistance in the identification of new drugs. Alternatively, the study of characteristic molecule fragments combined with the determination of their accurate masses can be a useful approach to identify unknown samples not previously analysed.

Micro extraction by packed sorbent coupled to liquid chromatography tandem mass spectrometry for the rapid and sensitive determination of cannabinoids in oral fluids.

The evaluation of oral fluids (OFs) levels is useful in proving drug consumption, particularly for monitoring abuse in workplaces and for the driving under the influence of drugs (DUIDs) programs. OF is a complex matrix and a small amount of sample is available, especially after cannabis smoking. This paper reports a method for the determination of cannabinoids and metabolites in OF: THC, 11-hydroxy-THC (OH-THC) and THC-COOH. Cannabidiol (CBD) and cannabinol (CBN) were also detected by LC-MS/MS. The OF pre-treatment was based on micro-extraction by packed sorbent (MEPS), a recently developed solid phase extraction technique which operates with small sample volumes: only 125μL of sample was required, allowing the collection by simple expectoration. Analytes elution was achieved using 2×25μL of 50mM NH4OH in methanol. A rapid and effective clean-up has been obtained with satisfactory recovery values and a negligible matrix effect. The LOQs ranged between 0.020ngmL(-1) for THC-COOH and 0.40ngmL(-1) for OH-THC. The chromatographic conditions obtained with a fused-core column allowed a good separation of the analytes in 6min only. The whole procedure has been validated according to SOFT/AAFS guidelines.

A snapshot on NPS in Italy: Distribution of drugs in seized materials analysed in an Italian forensic laboratory in the period 2013–2015

The diffusion of New Psychoactive Substances (NPS) in the illicit drug market is a worldwide problem. The aim of the study is to describe the qualitative distribution of drugs of abuse in seized materials confiscated in the Italian territory over the last two years. Between 2013 and 2015 162 seizures of substances purchased through the Internet and confiscated by police authorities were analyzed: 35 seizures (22%) were crystals of 3-methylmethcathinone (3-MMC). Although 3-MMC is subject to the relevant legislation in Italy, it is not controlled in other countries such as the Netherlands, from which the shipments originated. 33 seizures (20%) were crystals of 4-methylethcathinone (4-MEC), 19 seizures (12%) were powders containing methylenedioxypyrovalerone (MDPV). N,N-diallyl-5-methoxytryptamine (5-MeO-DALT) was identified in 5 powders, whereas ethylphenidate in six and pyrrolidinophenones in fourteen seized powders: 6 α-PVP (alpha-pyrrolidinovalerophenone), 6 α-PHP (alpha-pyrrolidinohexiophenone) and 1 α-PVT (alpha-pyrrolidinopentiothiophenone). Other substances identified were cathinones such as pentedrone, methylone, buthylone, ethylone, methedrone, 3-CMC (3-chloromethcathinone), 3,4-dimethylmethcathinone (3,4-DMMC), flephedrone (4-fluoromethcathinone or 4-FMC), 2-FMC and 3-FMC (2- and 3-fluoromethcathinone), MPPP (4-methyl-alpha-pyrrolidinopropiophenone), bk-2C-B (2-amino-1-(4-bromo-2,5-dimethoxyphenyl)ethan-1-one). Other compounds were NM2AI (N-methyl-2-aminoindane), MPA (1-(thiophen-2-yl)-2-methylaminopropane), MTTA (mephtetramine), 4-APB and 6-APB (4- and 6- (2-aminopropyl)benzofuran), 2-fluoromethamphetamine, 1mCPP (1-meta-chlorophenylpiperazine) and diphenidine, detected for the first time in Europe. Only three seizures contained synthetic cannabinoids, consisting of herbal blends soaked in N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (AKB48), or a mixture of 5-F-AKB48 and BB-22 (1-(cyclohexylmethyl)-8-quinolinyl ester-1H-indole-3-carboxylic acid). In some mixtures of drugs - such as granules - 4-MEC and pentedrone were detected, also with traces of diphenidine on one occasion. In other cases 5-MeO-DALT, ethylphenidate and caffeine were mixed together. In one batch, the mixture was flephedrone and methoxethamine, whereas in another one the sample contained methylone, ethylone, methedrone, 4-fluoroamphetamine, 5-MeO-DALT and 5MeO-MiPT (N-methyl-N-isopropyl-5-methoxytryptamine). In 9 seizures, tablets shipped together with NPS were also found to contain sildenafil. The analyses performed on these seizures showed the presence of a wide number of NPS within the Italian boundaries coming from abroad, therefore this study confirms the threat for the public health, especially when the content of NPS being sold is not reported on the label or misleading.

Screening for new psychoactive substances in hair by ultrahigh performance liquid chromatography-electrospray ionization tandem mass spectrometry

In the latest years, many new psychoactive substances (NPS) from several drug classes have appeared in the illicit drug market. Their rapid, sensitive and specific identification in biological fluids is hence of great concern for clinical and forensic toxicologists. Here is described a multi-analyte method for the determination of NPS, pertaining to different chemical classes (synthetic cannabinoids, synthetic cathinones, ketamine, piperazines and amphetamine-type substances-ATS) in human hair using ultrahigh performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) in electrospray ionization mode. We focused on a sample preparation able to extract the different classes of NPS. About 30mg of hair was decontaminated and incubated overnight under sonication in different conditions depending on the type of analytes to be extracted: (a) with 300μL of HCOOH 0.1% for cathinones, piperazines and ATS; (b) with 300μL of MeOH for synthetic cannabinoids. Ten microliter of the extracts were then injected in UHPLC-ESI-MS/MS in MRM mode. The LODs varied from 2pg/mg to 20pg/mg. The method was linear in the range from the LOQ to 500pg/mg and showed acceptable precision (%RSD<15) and accuracy (%E<15) for all the analytes. The method was finally applied on 50 samples from real forensic cases (driving license re-granting, postmortem toxicological analyses, workplace drug testing). In three samples we detected synthetic cannabinoids, in four samples cathinones or ephedrines, in two samples ketamine.

High-throughput screening for new psychoactive substances (NPS) in whole blood by DLLME extraction and UHPLC-MS/MS analysis

The increasing number of new psychoactive substances (NPS) present in the illicit market render their identification in biological fluids/tissues of great concern for clinical and forensic toxicology. Analytical methods able to detect the huge number of substances that can be used are sought, considering also that many NPS are not detected by the standard immunoassays generally used for routine drug screening. The aim of this work was to develop a method for the screening of different classes of NPS (a total of 78 analytes including cathinones, synthetic cannabinoids, phenethylamines, piperazines, ketamine and analogues, benzofurans, tryptamines) from blood samples. The simultaneous extraction of analytes was performed by Dispersive Liquid/Liquid Microextraction DLLME, a very rapid, cheap and efficient extraction technique that employs microliters amounts of organic solvents. Analyses were performed by a target Ultrahigh Performance Liquid Chromatography tandem Mass Spectrometry (UHPLC-MS/MS) method in multiple reaction monitoring (MRM). The method allowed the detection of the studied analytes with limits of detection (LODs) ranging from 0.2 to 2ng/mL. The proposed DLLME method can be used as an alternative to classical liquid/liquid or solid-phase extraction techniques due to its rapidity, necessity to use only microliters amounts of organic solvents, cheapness, and to its ability to extract simultaneously a huge number of analytes also from different chemical classes. The method was then applied to 60 authentic real samples from forensic cases, demonstrating its suitability for the screening of a wide number of NPS.

Screening for exogenous androgen anabolic steroids in human hair by liquid chromatography/orbitrap-high resolution mass spectrometry

A method for the screening of various anabolic steroids and their esters in human hair, based on liquid-chromatography-high resolution mass spectrometry using an Exactive benchtop Orbitrap mass spectrometer, has been set up and validated. This method involved methanolic incubation of 30 mg of hair and analysis of the relevant extract in HPLC using a C18 column. The mass detector, with nominal resolving power of 100,000, operated in full scan mode in APCI under positive ionization mode. Analytes were identified by exact mass, correspondence of isotopic cluster and retention times. The limits of detection obtained varied from 10 to 50 pg mg(-1), and limits of quantitation were 0.5 ng mg(-1) for all compounds. The method was linear for all analytes in the ranges from the LOQ to 6 ng mg(-1), giving correlation coefficients >0.99 for all analytes. Also accuracy (intended as %E) and repeatability (%CV) were always lower than 15%. Specificity was assessed by analysing ten blank samples and fifteen samples from polidrug abusers. This method was applied to a real-life case, resulting in the identification of testosterone undecanoate in the hair of a suspect. The analyte identity was confirmed by the analysis of its in-source fragmentation and comparison to a certified standard. Thanks to the scan acquisition, this method also enables retrospective re-analysis of the acquired datafile in case a further analyte needs to be screened.

Simplifying sample pretreatment: Application of dried blood spot (DBS) method to blood samples, including postmortem, for UHPLC–MS/MS analysis of drugs of abuse ☆

The complexity of biological matrices, such as blood, requires the development of suitably selective and reliable sample pretreatment procedures prior to their instrumental analysis. A method has been developed for the analysis of drugs of abuse and their metabolites from different chemical classes (opiates, methadone, fentanyl and analogues, cocaine, amphetamines and amphetamine-like substances, ketamine, LSD) in human blood using dried blood spot (DBS) and subsequent UHPLC-MS/MS analysis. DBS extraction required only 100μL of sample, added with the internal standards and then three droplets (30μL each) of this solution were spotted on the card, let dry for 1h, punched and extracted with methanol with 0.1% of formic acid. The supernatant was evaporated and the residue was then reconstituted in 100μL of water with 0.1% of formic acid and injected in the UHPLC-MS/MS system. The method was validated considering the following parameters: LOD and LOQ, linearity, precision, accuracy, matrix effect and dilution integrity. LODs were 0.05-1ng/mL and LOQs were 0.2-2ng/mL. The method showed satisfactory linearity for all substances, with determination coefficients always higher than 0.99. Intra and inter day precision, accuracy, matrix effect and dilution integrity were acceptable for all the studied substances. The addition of internal standards before DBS extraction and the deposition of a fixed volume of blood on the filter cards ensured the accurate quantification of the analytes. The validated method was then applied to authentic postmortem blood samples.

A μ-SPE procedure for the determination of cannabinoids and their metabolites in urine by LC–MS/MS

In this paper the development and validation of a method for the analysis of THC-COOH, THC, THC-OH, CBD and CBN in their total form in urine by LC-MS/MS is presented. Tandem hydrolysis, i.e. enzymatic and basic, has been found optimal for the simultaneous analysis of the selected analytes in urine: basic hydrolysis is more effective for the cleavage of THC-COOH glucuronide while enzymatic hydrolysis allows the cleavage of the conjugated cannabinoids possessing ether bonds (THC, THC-OH, CBD). The whole procedure requires a 2h enzymatic hydrolysis using only 90μL of urine by μ-SPE extraction technique with C18 tips. Clear advantages in terms of time and of enzyme reduction are obtained and the cost of the analysis can be dramatically reduced. Satisfactory recovery values and matrix effect are obtained, and the chromatographic run, performed with a fused-core column, allowed the complete analyte separation in only 3min (total run 5.8min) with a common HPLC system. Furthermore the whole procedure has been validated according to SWGTOX guidelines: LOQs are between 6 and 10ppb, quite lower than the requested cut-off for urine testing; intermediate reproducibility of the selected analytes is below 10% and accuracy is between 85% and 113%, except for CBD, included only for semi-quantitative determination.

Liquid chromatography-high resolution mass spectrometry (LC-HRMS) determination of stimulants, anorectic drugs and phosphodiesterase 5 inhibitors (PDE5I) in food supplements

The paper describes a liquid chromatography/high resolution mass spectrometry LC/HRMS method for the simultaneous identification and quantification of stimulants (ephedrines, caffeine, anorectic drugs such as phentermine, phendimetrazine, phenmetrazine, fenfluramine, benfluorex, mephentermine, fencanfamine, sibutramine) and PDE5I (sildenafil, vardenafil and tadalafil) in food supplements using a benchtop Orbitrap mass spectrometer. The mass detector, with a nominal resolving power of 100,000 (FWHM at m/z 200), operated in full scan mode in ESI positive ionization mode. Analytes were identified by retention times, accurate masses and correspondence of experimental and calculated isotopic patterns. The limits of detection (LOD) obtained varied from 1 to 25 ng g(-1) and limits of quantification (LOQ) were 50 ng g(-1) for all compounds. The method was linear for all the analytes in the ranges from 50 to 2000 ng g(-1), giving correlation coefficients>0.99. Accuracy (intended as %E) and repeatability (% CV) were always lower than 15%. The method was applied to the analysis of 36 dietary supplements, revealing the presence of ephedrine and/or pseudoephedrine in four of them, caffeine in eight of them and sildenafil in four of them. In one case, ephedrine was not reported on the label of the dietary supplement, as well as for caffeine in other two cases. A further confirmation of the analytes identity in positive samples was obtained through in-source fragmentation and comparison of the obtained fragments and their relative abundances with those from certified standards. As the acquisition mode is full scan, it would be also possible to re-process a previously acquired datafile for the investigation of untargeted analytes.

Determination of anabolic agents in dietary supplements by liquid chromatography-high-resolution mass spectrometry

A sensitive method for the identification and quantification of anabolic steroids and clenbuterol at trace levels in dietary supplements by liquid chromatography-high-resolution mass spectrometry (LC-HRMS) in atmospheric pressure ionisation (APCI) mode using a single-stage Orbitrap analyser operating at a resolution power of 100 000 full width at half maximum (FWHM) was developed and validated. A total of 1 g of dietary supplement was added with testosterone-d3 as internal standard, dissolved in methanol, evaporated to dryness, diluted in sodium hydroxide solution and extracted with a mixture of pentane/ethyl ether 9:1. The extract was directly injected into the LC-HRMS system. The method was fully validated. Limits of detection (LODs) obtained for anabolic androgenic steroids (AASs) varied from 1 to 25 ng g−1 and the limit of quantitation (LOQ) was 50 ng g−1 for all analytes. The calibration was linear for all compounds in the range from the LOQ to 2000 ng g−1, with correlation coefficients always higher than 0.99. Accuracy (intended as %E) and repeatability (%CV) were always lower than 15%. Good values of matrix effect and recovery were achieved. The ease of the sample preparation together with a fast run time of only 16 min permitted rapid identification of the analytes. The method was applied to the analysis of 30 dietary supplements in order to check for the presence of anabolic agents not labelled as being present in these supplements. Many AASs were often detected in the same sample: indeed, androstenedione was detected in nine supplements, 5-androsten-3β-ol-17-one (DHEA) in 12, methandienone in three, stanozolol in one, testosterone in seven and testosterone esters in four of them. A retrospective analysis of suspected compounds not included at the beginning of the method development was also possible by means of the full acquisition spectra obtained with the HRMS technique. Graphical Abstract