Metabolite elucidation of 2-fluoro-deschloroketamine (2F-DCK) using molecular networking across three complementary in vitro and in vivo models.
Drug testing and analysis – January 01, 2022
Source: PubMed
Summary
Crucially, specific metabolites of the new psychoactive substance 2F-DCK can now improve forensic detection. Investigating its metabolism using a HepaRG cell line and human liver microsomes, combined with molecular networking, revealed thirteen metabolites *in vitro*. These experiments, involving incubations up to 24 hours, yielded vital metabolic profiles. Subsequently, seven additional metabolites were identified in a post-mortem case, including three minor Phase II metabolites. The findings propose that nor-2F-DCK and a hydrogenated metabolite be added to HRMS libraries, significantly enhancing the ability to detect 2F-DCK use.
Abstract
This work first aims to investigate metabolites of 2-fluoro-deschloroketamine (2F-DCK), a new arylcyclohexylamine derivatives (a group of dissociative ketamine-based substances) using two in vitro experimental approaches, and to compare obtained results by means of molecular networking. Metabolites of 2F-DCK were investigated using both human liver microsomes (HLMs) and hepatic (HepaRG) cell line incubates using molecular networking approach: 2F-DCK pure substance was incubated with HLMs for up to 1 h at two concentrations (100 and 500 μM) and with HepaRG cells for two time periods (8 and 24 h) at one concentration (20 μM). In vitro obtained results were subsequently applied to a 2F-DCK-related fatality case. In vitro-produced metabolites were investigated using high-resolution accurate mass spectrometry using Orbitrap mass analyzer technology. Thirteen metabolites were in vitro produced and several metabolic pathways can be postulated. Seven additional metabolites were found in post-mortem samples (bile and urine) of the case, comprising three Phase II metabolites, which appear to be minor in vivo metabolites. HLMs and HepaRG cell models appear to be complementary and obtained data allowed the identification of several specific 2F-DCK metabolites in biological samples. In practical terms, observed metabolic ratios suggested that nor-2F-DCK (208.1137 m/z) and a hydrogenated metabolite (224.1443 m/z) could be proposed as reliable metabolites to be recorded in HRMS libraries in order to improve detection of 2F-DCK use.