Development and validation of a color spot test method for the presumptive detection of 25‐NBOMe compounds

Abstract

The great increase of new psychoactive substances over the past decade has substantially transformed the illicit drug industry to an ever-changing dynamic market. 25-NBOMe compounds are just one of these new substance groups that pose a public health risk in many countries around the world. These highly potent, hallucinogenic phenethylamines have previously been sold as "legal highs" or "synthetic LSD" and the necessity to rapidly identify their presence is crucial.While there are many laboratory-based analytical methods capable of identifying these compounds, the lack of presumptive test methods indicates the need for a specific and timely test that could be used in the field. Herein we outline the developed chemical spot test that can selectively identify the presence of 25-NBOMe compounds and related analogs through the reaction with a substituted benzoquinone reagent under basic conditions. This test method has been comprehensively validated showing a high level of selectivity, specificity, and precision with only two other illicit substances producing similar positive results as 25-NBOMe and few false-negative results seen. The working limit of detection was determined to be 225 μg and there was no cross-reactivity from potential adulterants of significance. This test has also been shown to work directly with blotter papers containing 25-NBOMe compounds, indicating no interference from this common matrix and the ability to differentiate these compounds from LSD. This method shows a high potential to be translated to a field compatible test that is simple, rapid, and selective for 25-NBOMe compounds.

Interpol Review of Drug Analysis 2019-2022

“…2019 analytical differentiation of the indole ring regioisomeric chloro-1-n-pentyl-3-(1-naphthoyl)-indoles by CG-MS and GC-IR [ 685 ]; Simultaneous LC-MS/MS analysis of 2Cs, 25-NBOHs, 25-NBOMes and LSD in seized exhibits [ 686 ]; MALDI-MS and MALDI-MSD were coupled to a FT-ICR MS to analyze seven blotter papers of NBOMes containing 25I–NBOH and 251-NBOMe [ 687 ]; an electrochemical method using a SPCE for the detection and full differentiation of 25I–NBOMe, 25I–NBOH and 2C–I [ 688 ]; four halide derivatives of NBOMe, namely, 2-(4-fluoro-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethan-1-amine, 2-(4-chloro-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl) ethan-1-amine, 2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-methoxybenzypethan-1-amine, and 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2-methoxybenzyl)ethan-1-amine, were detected and quantified simultaneously using HPLC, and PAD and AD two detection systems were compared [ 689 ]; review of the main methods for the analysis of NBOMe in their chemical structures for detection in seized and biological materials for forensic and clinical purposes [ 690 ]; analysis of the fragmentation patterns of NBOMe derivatives using LC-QTOF-MS [ 691 ]; 2020 Fragmentation challenges in the identification of thermolabile NBOH compounds [ 692 ]; comprehensive triple quadrupole MS/MS protocol coupled to LC and GC, for rapid screening and quantitation of NBOMes and NBOHs in seized blotter paper [ 693 ]; an additive manufacturing 3D printed wall-jet flow cell for use with HPLC-AD for the detection and quantification of various a NBOMes [ 694 ]; use of short analytical columns (4 and 10 m) to decrease compound degradation in the GC oven during chromatographic separation to allow the analysis of non-derivatized 25R–NBOH compounds by GC-MS [ 695 ]; synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of 25I–NBOMe [ 696 ]; Synthesis and determination of analytical characteristics and differentiation of positional isomers in the series of NBOMes using chromatography-mass spectrometry [ 697 ]; analysis of blotter paper samples containing 25I–NBOMe and 25C–NBOMe using complementary techniques including micro x-ray fluorescence (mu XRF), LA-ICP-OES, MALDI-MS, and LC-MS [ 698 ]; review [ 699 ]; review of 25I–NBOMe [ 700 ]; review of 25C–NBOMe [ 701 ]; identification of a new class of thermolabile psychoactive compounds, 4-substituted 2-(4-X-2, 5-dimethoxyphenyl)-N- [(2-hydroxyphenyl)methyl] ethanamine (25X–NBOH, X = Cl, Br, or I) by GC-MS using chemical derivatization by heptafluorobutyric anhydride (HFBA) [ 702 ]; identification and structural elucidation of three NBOHs detected in seized blotter papers (25B–NBOH, 25C–NBOH, and 25E-NBOH) using FTIR, GC-MS, LC-MS/MS and NMR spectroscopy [ 703 ]; 2021 chemical color spot test that can selectively identify the presence of 25-NBOMe compounds and related analogues [ 704 ]; synthesis method for NBOHs (25H-, 25I- and ...…”

Portable testing techniques for the analysis of drug materials

“…However, false positive and false negative color test results can occur as a result of incorrect application of the color test kit, harsh environmental conditions under which the test is performed, and complex sample mixtures. The emergence of NPS, often disguised as traditional recreational drugs, have led to color test validation studies to determine the effectiveness and potential cross-reactivities of current test methods (Cuypers et al, 2016), and the introduction of new chemical color test methods for NPS such as piperazine derivatives (Philp et al, 2013), synthetic cathinones (Philp et al, 2016), and N-methoxybenzylmethoxyphenylethylamines (NBOMes) (Clancy et al, 2021). Despite the relatively low selectivity of chemical color tests, their use has continued for decades owing to their simplicity, rapidity, and portability.…”

Identification of synthetic cathinones in seized materials: A review of analytical strategies applied in forensic chemistry

“…According to SWGDRUG guidelines, color tests can provide analytical selectivity through obtaining general or chemical class‐related information (SWGDRUG, 2019). These tests present some analytical benefits including easy and quick execution, no need for instrumentation, low costs for execution and the possibility of execution in diverse settings, including on‐site, outside the laboratory environments (Clancy et al, 2020; Philp & Fu, 2018). In general, color tests exhibit good sensitivity and can reach the microgram range, which depends on the type of drug and reagent (Harper et al, 2017).…”

“…As previously approached, many NPS are structurally related to other “traditional” drugs of abuse. Therefore, there is a potential issue with regard to the selectivity of color tests when an NPS may be involved (Clancy et al, 2020), with the traditional, common color tests being poorly specific to these new drugs (Philp & Fu, 2018), especially considering that many synthetic cathinones are similar to other traditional, well‐known drugs, such as the amphetamines. Moreover, a color test might not be available yet for a class of NPS or not be appropriate (Sisco et al, 2021), which applies to the synthetic cathinones as well.…”