NBOMe compounds: An overview about analytical methodologies aiming their determination in biological matrices

Acute, chronic, and post-mortem toxicity: a review focused on three different classes of new psychoactive substances

PURPOSE

New psychoactive substances (NPS) are not controlled under the Single Convention on Narcotic Drugs of 1961 or the 1971 Convention, but they may pose a public health threat. Knowledge of the main properties and toxicological effects of these substances is lacking. According to the current Drugs Law (Law n. 11.343/2006), the Brazilian Surveillance Agency issues directives for forbidden substances in Brazil, and structural classes of synthetic cannabinoids, cathinones, and phenylethylamines are considered illicit drugs. Considering that data on these controlled substances are scattered, the main objective of this work was to collect and organize data to generate relevant information on the toxicological properties of NPS.

METHODS

We carried out a literature review collecting information on the acute, chronic, and post-mortem toxicity of these classes of NSP. We searched info in five scientific databases considering works from 2017 to 2021 and performed a statistical evaluation of the data.

RESULTS

Results have shown a general lack of studies in this field given that many NPS have not had their toxicity evaluated. We observed a significant difference in the volume of data concerning acute and chronic/post-mortem toxicity. Moreover, studies on the adverse effects of polydrug use are scarce.

CONCLUSIONS

More in-depth information about the main threats involving NPS use are needed.

Target and suspect screening of (new) psychoactive substances in South Korean wastewater by LC-HRMS

New psychoactive substances (NPS) are a type of abused drug designed to mimic the effects of the currently known illicit drugs, whose structures are constantly changing to escape surveillance. The quick identification of NPS use in the community therefore demands immediate action. This study aimed to develop a target and suspect screening method using LC-HRMS to identify NPS in wastewater samples. An in-house database of 95 traditional and NPS was built using the reference standards, and an analytical method was developed. Wastewater samples were collected from 29 wastewater treatment plants (WWTP) across South Korea, representing 50 % of the total population. The psychoactive substances in waste water samples were screened using in-house database and developed analytical methods. A total of 14 substances were detected in the target analysis, including three NPS (N-methyl-2-AI, 25E-NBOMe, and 25D-NBOMe) and 11 traditional psychoactive substances and their metabolites (zolpidem phenyl-4-COOH, ephedrine, ritalinic acid, tramadol, phenmetrazine, phendimetrazine, phentermine, methamphetamine, codeine, morphine, and ketamine). Out of these, N-methyl-2-AI, zolpidem phenyl-4-COOH, ephedrine, ritalinic acid, tramadol, phenmetrazine, and phendimetrazine were detected with a detection frequency of over 50 %. Primarily, N-methyl-2-Al was detected in all the wastewater samples. Additionally, four NPSs (amphetamine-N-propyl, benzydamine, isoethcathinone, methoxyphenamine) were tentatively identified at level 2b in a suspect screening analysis. This is the most comprehensive study to investigate NPS using target and suspect analysis methods at the national level. This study raises a need for continuous monitoring of NPS in South Korea.

Determination of synthetic hallucinogens in oral fluids by microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry

A fast and simple procedure based on microextraction by packed sorbent (MEPS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been developed for the simultaneous quantification of 28 synthetic hallucinogens in oral fluids, including lysergic acid diethylamide and substances from NBOMe, NBOH, NBF, 2C, and substituted amphetamine categories. Extraction conditions such as type of sorbent, sample pH, number of charge/discharge cycles, and elution volume were studied. Hallucinogenic compounds were extracted from oral fluid samples using C18 MEPS, loading with 100 μL sample (adjusted to pH 7) in 3 cycles, washing with 100 μL deionized water, and eluting with 50 μL methanol in 1 cycle, giving quantitative recoveries and no significant matrix effects. Limits of detection from 0.09 to 1.22 μg L^-1; recoveries from 80 to 129% performed in spiked oral fluid samples at 20, 50, and 100 μg L^-1; and high precision with relative standard deviations lower than 9% were obtained. The proposed methodology was demonstrated to be appropriate for the simple and sensitive determination of NBOMe derivates and other synthetic hallucinogenic substances in oral fluid samples.

Potential of chromatography and mass spectrometry for the differentiation of three series of positional isomers of 2-(dimethoxyphenyl)-N-(2-halogenobenzyl)ethanamines

N-(2-Substituted benzyl)-2,5-dimethoxyphenethylamines often cause severe poisonings which has led to their legal prohibition in many countries. At the same time, their positional isomers can be studied as potential therapeutic drugs. In this regard, the search for various approaches to differentiate these isomers is an important practical task, the solution of which would guarantee from identification errors during laboratory analysis. In this paper, the possibilities of differentiation of isomers varying in the position of two methoxy groups in the phenylethyl part of the molecule are considered on the example of compounds of NBF, NBCl and NBBr series by chromatography-mass spectrometry methods. Gas or liquid reverse-phase chromatography in the proposed chromatographic separation modes has demonstrated their ability to resolve this problem reliably. Data on retention indices of isomeric compounds and their derivatives can serve as an additional identification criterion for gas chromatography-mass spectrometry (GC-MS) analysis. Differentiation of NBF and NBCl isomers using electron ionization (EI) mass spectra is feasible only if both the spectrum of the compound and its N-trifluoroacetyl derivative are registered; differentiation of NBBr positional isomers under these conditions does not require obtaining the derivatives. Using electrospray ion source, the compounds can easily be differentiated based on the distinctive features of their collision induced dissociation (CID) spectra recorded at low energy values, which also does not require the synthesis of derivatives. The data presented in current paper will be useful for analysis in laboratories providing the determination of narcotic drugs.

Application of Homogeneous Liquid-Liquid Microextraction with Switchable Hydrophilicity Solvents to the Determination of MDMA, MDA and NBOMes in Postmortem Blood Samples

Synthetic drugs for recreational purposes are in constant evolution and their consumption promote a significant increase in intoxication cases, resulting in damaging public health. The development of analytical methodologies to confirm the consumption of illicit drugs in biological matrices are required for control of these substances. This work exploited the development of an extraction method based on homogenous liquid-liquid microextraction with switchable hydrophilicity solvent as extraction phase (SHS-HLLME) for the determination of the synthetic drugs MDMA, MDA and NBOMes (25B, 25C and 25I) in postmortem blood, followed by liquid chromatography coupled to mass spectrometry in tandem (LC-MS/MS). The optimized sample preparation conditions consisted of using 250 µL of ZnSO4 10% and 50 µL of NaOH 1 mol/L in the protein precipitation step; N,N-dimethylcyclohexylamine (DMCHA) was used as switchable hydrophilicity solvent (SHS), 650 μL of a mixture of SHS:HCl 6 mol/L (1:1 v/v), 500 μL of whole blood, 500 μL of NaOH 10 mol/L and 1 min of extraction time. The proposed method was validated, providing determination coefficients higher than 0.99 for all analytes; LOD and LOQ ranged from 0.1 to 10 ng/mL; intra-run precision from 2.16 to 9.19%; inter-run precision from 2.39 to 9.59%; bias from 93.57 to 115.71%; and matrix effects from 28.94 to 51.54%. The developed method was successfully applied to four authentic postmortem blood samples from synthetic drugs users, and it was found to be reliable with good selectivity.

A quantitative method for the selective 5-HT2A agonist 25CN-NBOH in rat plasma and brain

In recent years, agonists of the 5-HT_2A receptor have gained increasing attention for their potential therapeutic use to treat psychological disorders such as anxiety and depression. Here, we report the development and validation of an LC-MSMS based analytical method for the quantification of the novel selective 5-HT_2A agonist 25CN-NBOH in rat plasma and brain. As simple and efficient sample clean-up we applied the Phree Phospholipid Removal approach from Phenomenex, which is particularly novel for brain samples. In order to investigate the metabolic stability of 25CN-NBOH in vitro biotransformation studies with recombinant enzymes and human liver microsomes were conducted. Several biotransformation products and pathways could be identified. Based on the in vitro study one of the putative metabolites (2C-CN) was included in the analytical method development. To test the methods applicability 25CN-NBOH was quantified in plasma and brain samples from a pharmacokinetic in vivo study with Wildtype Long Evans rats. Both the in vitro metabolism data as well as the in vivo PK data suggest that 25CN-NBOH is susceptible to metabolism, but is degraded slower and is more stable compared to other NBOMe's investigated to date. The developed analytical method might serve as basis to include further 25CN-NBOH metabolites. It is expected to facilitate further preclinical and clinical investigations of 25CN-NBOH in biological matrices.

Recent bionalytical methods for the determination of new psychoactive substances in biological specimens

One of the problems associated with the consumption of new psychoactive substances is that in most scenarios of acute toxicity the possibility of quick clinical action may be impaired because many screening methods are not responsive to them, and laboratories are not able to keep pace with the appearance of new substances. For these reasons, developing and validating new analytical methods is mandatory in order to efficiently face those problems, allowing laboratories to be one step ahead. The goal of this work is to perform a critical review regarding bionalytical methods that can be used for the determination of new psychoactive substances (phenylethylamines, cathinones, synthetic cannabinoids, opioids, benzodiazepines, etc), particularly concerning sample preparation techniques and associated analytical methods.

Exploring the chemical profile of designer drugs by ESI(+) and PSI(+) mass spectrometry-An approach on the fragmentation mechanisms and chemometric analysis

The consumption of design drugs, frequently known as new psychoactive substances (NPS), has increased considerably worldwide, becoming a severe issue for the responsible governmental agencies. These illicit substances can be defined as synthetic compounds produced in clandestine laboratories in order to act as analogs of schedule drugs mimetizing its chemical structure and improving its pharmacological effects while hampering the control and making regulation more complicated. In this way, the development of new methodologies for chemical analysis of NPS drugs is indispensable to determine a novel class of drugs arising from the underground market. Therefore, this work shows the use of high-resolution mass spectrometry Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) applying different ionization sources such as paper spray ionization (PSI) and electrospray ionization (ESI) in the evaluation of miscellaneous of seized drugs samples as blotter paper (n = 79) and tablet (n = 100). Also, an elucidative analysis was performed by ESI(+)MS/MS experiments, and fragmentation mechanisms were proposed to confirm the chemical structure of compounds identified. Besides, the results of ESI(+) and PSI(+)-FT-ICR MS were compared with those of GC-MS, revealing that ESI(+)MS showed greater detection efficiency among the methodologies employed in this study. Moreover, this study stands out as a guide for the chemical analysis of NPS drugs, highlighting the differences between the techniques of ESI(+)-FT-ICR MS, PSI(+)-FT-ICR MS, and GC-MS.

Interpol review of controlled substances 2016-2019

This review paper covers the forensic-relevant literature in controlled substances from 2016 to 2019 as a part of the 19th Interpol International Forensic Science Managers Symposium. The review papers are also available at the Interpol website at: https://www.interpol.int/content/download/14458/file/Interpol%20Review%20Papers%202019.pdf.