A química dos cogumelos alucinógenos: Desenvolvimento de um método de extração da substância psilocina em matrizes forenses

Abstract

Hallucinogenic mushrooms (HM) are drugs of abuse that affect the central nervous system. The substance psilocin (PSI) is the dephosphorylated form of psilocybin (PSB) and is responsible for the hallucinogenic effects of mushrooms of the Psilocybe genus. These substances are thermolabile, which hinders their extraction by conventional techniques and analysis through gas chromatography, limiting the development of specific processes. Therefore, the objective of this study was to develop a method for extracting psilocin from HM using ultrasound-assisted extraction followed by analysis through gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). To achieve this, solvents and modifiers were evaluated for the extraction of PSI using statistical tools (ANOVA and Tukey’s HSD). The solvents tested were: hexane, dichloromethane, chloroform, acetone, ethyl acetate, and methanol; and the modifiers: ammonium hydroxide, acetic acid, and hydrochloric acid. Subsequently, a Design of Experiments fractional factorial (DoE) was conducted to analyze the variables: extraction time (min), number of extraction cycles, solvent-to-sample ratio (g:mL), and modifier concentration (%). All stages of development and optimization used the absolute chromatographic area of PSI as the response variable. Finally, qualitative and quantitative analyses of PSI were performed on three edible mushroom samples and five seized samples provided by the Civil Police of the State of Rio de Janeiro (PCERJ). Based on the DoE, the optimized extraction conditions were: 10 minutes of extraction, 1 extraction cycle, solvent-to-sample ratio of 5:1 (g:mL), and modifier concentration of 6%. The concentrations found in the seized samples ranged from 0.0045 to 0.03279 µg mL⁻¹. PSI was not detected in any of the edible mushroom samples. Considering that GC-MS/MS is the most commonly used technique in forensic analysis, the developed method enables an increase in the number of analyses with higher analytical sensitivity for samples seized by PCERJ, allowing for better monitoring of the occurrence of illegal seizures of this matrix.