Chemical identification of cannabinoids in street marijuana samples using electrospray ionization FT-ICR mass spectrometry

Abstract

The Cannabis sativa L. plant is a species rich in a variety of cannabinoid compounds and Δ⁹-tetrahydrocannabinol (Δ⁹-THC) has been reported as a main psychotropic substance. In this study, electrospray ionization (ESI), coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), was used in order to perform a direct and fast analysis of street marijuana samples. ESI(−)-FT-ICR MS detected 21 cannabinoid species in the deprotonated form, [M − H]⁻. Other species were detected in regions of m/z 600–800 and 800–1000, corresponding to dimers and trimers of cannabinoids. In addition, ESI(−) was better able to analyze the chemical profile of terpenophenolic species (C_cH_hO_o) than ESI(+). ESI(+)-FT-ICR MS detected the presence of adulterants such as cocaine, lidocaine, and nicotine. Finally, the sensitivity of fast blue B colorimetric testing was also evaluated and the results were compared to the ESI(−)FT-ICR MS data.