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NMR Spectroscopic Reference Data of Synthetic Cannabinoids Sold on the Internet
Eva-Maria Hubner1, Martin G Schmid1, Verina Manojlovic1
1Institute of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, University of Graz, Graz, Austria.
Magnetic Resonance in Chemistry : MRC
|January 2, 2025
Summary
Online synthetic cannabinoid products are often mislabeled and contain uncharacterized substances. This study identified 21 synthetic cannabinoids from 25 online samples, including novel compounds, highlighting significant issues in product authenticity and regulation.
Area of Science:
- Forensic Chemistry
- Pharmacology
- Analytical Chemistry
Background:
- New psychoactive substances (NPSs), particularly synthetic cannabinoids, represent a rapidly growing class of drugs available globally.
- Unlike traditional illicit drugs, synthetic cannabinoids are often sold legally online due to structural differences from controlled substances like delta-9-tetrahydrocannabinol (Δ⁹-THC).
- These substances are frequently disguised as legal hemp products, herbal teas, or other plant materials, posing risks to consumers.
Purpose of the Study:
- To identify and characterize synthetic cannabinoid samples purchased online.
- To generate experimental data, including NMR-based structure elucidation, for previously uncharacterized or poorly documented synthetic cannabinoids.
- To assess the accuracy of product labeling for online synthetic cannabinoid purchases.
Main Methods:
- Procurement of 25 solid-state synthetic cannabinoid samples from various online vendors.
- Analysis using a combination of gas and liquid chromatography with mass spectrometric detection (GC-MS/LC-MS).
- Structure elucidation employing Nuclear Magnetic Resonance (NMR) spectroscopy.
Main Results:
- Analysis confirmed 21 of the 25 samples as synthetic cannabinoids.
- Thirteen identified synthetic cannabinoids lacked sufficient experimental NMR data in existing literature.
- One novel synthetic cannabinoid, CH-PIATA, was identified and characterized for the first time.
- Over 50% of the purchased samples were found to be falsely declared, indicating widespread mislabeling.
Conclusions:
- Online availability of synthetic cannabinoids is widespread, often with inaccurate labeling.
- A significant number of commercially available synthetic cannabinoids are novel or lack adequate characterization, posing analytical and regulatory challenges.
- The study underscores the urgent need for improved analytical methods and regulatory oversight for NPSs to ensure public safety.
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