Development of a semi-preparative LC method for the purification of synthetic cannabinoids impregnated in herbal products for chemical characterization by NMR and HRMS

Author(s)

de Araujo, Karen Rafaela Gonsalves ; Meirelles, Gabriela de Paula ; Demarque, Daniel Pecoraro ; Dorr, Fabiane ; Neves Junior, Luiz Ferreira ; Soares, Alexandre Learth ; Guedes, Camila Delanesi ; da Costa, Jose Luiz ; Yonamine, Mauricio

• Document type: Journal article
• Source: FORENSIC CHEMISTRY; v. 45, p. 9-pg., 2025-09-01.

Abstract

Synthetic cannabinoids (SCs) now encompass over 360 compounds under international control. Identifying these substances is a significant challenge for law enforcement, as they are new drugs found in herbal fragments, and reference standards are not available for traditional chemical analysis. To address this, substances can be identified using type A analytical techniques, according to the Scientific Working Group for the Analysis of Seized Drugs which are those with the highest level of selectivity and provide structural information, such as nuclear magnetic resonance and mass spectrometry. However, these methods require compound purification for proper characterization. This study aimed to develop a purification method for SCs in herbal fragments to enable chemical analysis. Seized samples were first analyzed using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS). Then, a semi-preparative liquid chromatography (LC) method was applied, successfully isolating SCs and allowing their structural determination through NMR and high-resolution mass spectroscopy. In the first sample, MDMB-CHMINACA was identified as the sole SC. In the second sample, GC-EI-MS analysis revealed a mass spectrum that did not match any library entry. After purification, the substance was identified as ADB-INACA. In the third sample, the method facilitated the separation and structural determination of four SCs (MDMB-INACA, ADB-BUTINACA, MDMB-4en-PINACA, and 5F-ADB) in a mixture from an herbal sample. In conclusion, the method developed for purification using semi-preparative LC for subsequent chemical characterization proved to be effective for the structural determination of new SCs present in herbal drugs seized by the police. (AU)

• FAPESP's process: 23/11314-8 - Development of a targeted and untargeted dynamic analytical strategy for the detection of new psychoactive substances in Forensic Toxicology
• Grantee: Gabriela de Paula Meirelles
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 24/02868-2 - Development of a "targeted" and "untargeted" dynamic analytical strategy for the detection of new psychoactive substances in Forensic Toxicology
• Grantee: Mauricio Yonamine
• Support Opportunities: Regular Research Grants