Development of a psilocin immunoassay for serum and blood samples

Development and validation of a sensitive LC-MS-MS method to quantify psilocin in authentic oral fluid samples

Psilocin is an active substance and a dephosphorylated product of psilocybin formed after the ingestion of mushrooms. The low stability caused by the quick oxidation of this analyte requires sensitive methods for its determination in biological matrices. In this work, we described the development, optimization and validation of a method for the quantification of psilocin in authentic oral fluid samples by liquid chromatography-tandem mass spectrometry. Liquid-liquid extraction was performed using 100 µL of oral fluid samples collected with a Quantisal™ device and t-butyl methyl ether as the extraction solvent. The method showed acceptable performance, with limits of detection and quantification of 0.05 ng/mL, and the calibration model was achieved between 0.05 and 10 ng/mL. Bias and imprecision results were below -14.2% and 10.7%, respectively. Ionization suppression/enhancement was lower than -30.5%, and recovery was >54.5%. Dilution integrity bias was <14.4%. No endogenous and exogenous interferences were observed upon analyzing oral fluid from 10 different sources and 56 pharmaceuticals and drugs of abuse, respectively. No carryover was observed at 10 ng/mL. Psilocin was stable in oral fluid at -20°C, 4°C and 24°C up to 24, 72 and 24 h, respectively, with variations <17.7%. The analyte was not stable after three freeze/thaw cycles, with variations between -73% and -60%. This suggests the instability of psilocin in oral fluid samples, which requires timely analysis, as soon as possible after the collection. The analyte remained stable in processed samples in an autosampler (at 10°C) for up to 18 h. The method was successfully applied for the quantification of five authentic samples collected from volunteers attending parties and electronic music festivals. Psilocin concentrations ranged from 0.08 to 36.4 ng/mL. This is the first work to report psilocin concentrations in authentic oral fluid samples.

Overview of the major classes of new psychoactive substances, psychoactive effects, analytical determination and conformational analysis of selected illegal drugs

The misuse of psychoactive substances is attracting a great deal of attention from the general public. An increase use of psychoactive substances is observed among young people who do not have enough awareness of the harmful effects of these substances. Easy access to illicit drugs at low cost and lack of effective means of routine screening for new psychoactive substances (NPS) have contributed to the rapid increase in their use. New research and evidence suggest that drug use can cause a variety of adverse psychological and physiological effects on human health (anxiety, panic, paranoia, psychosis, and seizures). We describe different classes of these NPS drugs with emphasis on the methods used to identify them and the identification of their metabolites in biological specimens. This is the first review that thoroughly gives the literature on both natural and synthetic illegal drugs with old known data and very hot new topics and investigations, which enables the researcher to use it as a starting point in the literature exploration and planning of the own research. For the first time, the conformational analysis was done for selected illegal drugs, giving rise to the search of the biologically active conformations both theoretically and using lab experiments.

Immunochemical monitoring of psilocybin and psilocin to identify hallucinogenic mushrooms

Development of rapid and reliable immunochemical methods for monitoring psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine; Pyb) and psilocin (dephosphorylated metabolite; Psi), the psychoactive compounds contained within hallucinogenic mushrooms (magic mushrooms), is desirable in order to identify these mushrooms and regulate their illicit use. Because no antibody was publicly available for this purpose, we generated two independent monoclonal antibodies (mAbs) against Pyb or Psi, and then developed enzyme-linked immunosorbent assays (ELISAs) by using them. To generate the specific antibodies, novel immunogenic conjugates were prepared by linking Pyb or Psi molecules to carrier proteins by modifying their 2-(N,N-dimethylamino)ethyl side chains. Spleen cells from mice immunized with these conjugates were fused with P3/NS1/1-Ag4-1 myeloma cells, and hybridoma clones secreting anti-Pyb and anti-Psi mAbs were established. These mAbs were characterized for their biochemical features and then applied to competitive ELISAs, which used microplates coated with Pyb or Psi linked with albumin. These ELISAs enabled the determination of Pyb or Psi with measurable ranges of ca. 0.20-20 or 0.040-2.0 μg/assay (limit of detection was 0.14 or 0.029 μg/assay), respectively. The related tryptamines were satisfactorily discriminated as exemplified by the cross-reactivity of the ELISA to determine Pyb (or Psi) with Psi (or Pyb) that were found to be 2.8 % (or <0.5 %), respectively. The Pyb and Psi contents in a dried powder of the hallucinogenic mushroom, Psilocybe cubensis, were determined to be 0.39 and 0.32 (w/w)%, respectively. The ELISAs developed using the current mAbs are promising tools for identifying illegal hallucinogenic mushrooms.

Direct Analysis of Psilocin and Muscimol in Urine Samples Using Single Drop Microextraction Technique In-Line with Capillary Electrophoresis

The fully automated system of single drop microextraction coupled with capillary electrophoresis (SDME-CE) was developed for in-line preconcentration and determination of muscimol (MUS) and psilocin (PSC) from urine samples. Those two analytes are characteristic active metabolites of Amanita and Psilocybe mushrooms, evoking visual and auditory hallucinations. Study analytes were selectively extracted from the donor phase (urine samples, pH 4) into the organic phase (a drop of octanol layer), and re-extracted to the acidic acceptor (background electrolyte, BGE), consisting of 25 mM phosphate buffer (pH 3). The optimized conditions for the extraction procedure of a 200 µL urine sample allowed us to obtain more than a 170-fold enrichment effect. The calibration curves were linear in the range of 0.05–50 mg L⁻¹, with the correlation coefficients from 0.9911 to 0.9992. The limit of detections was determined by spiking blank urine samples with appropriate standards, i.e., 0.004 mg L⁻¹ for PSC and 0.016 mg L⁻¹ for MUS, respectively. The limits of quantification varied from 0.014 mg L⁻¹ for PSC and 0.045 mg L⁻¹ for MUS. The developed method practically eliminated the sample clean-up step, which was limited only to simple dilution (1:1, v/v) and pH adjustment.

Biomedical analysis of New Psychoactive Substances (NPS) of natural origin

New psychoactive substances (NPS) can be divided into two main groups: synthetic molecules and active principles of natural origin. With respect to this latter group, a wide range of alkaloids contained in plants, mainly from Asia and South America, can be included in the class of NPS of natural origin. The majority NPS of natural origin presents stimulant and/or hallucinogenic effects (e.g. Catha edulis and Ayahuasca, respectively) while few of them show sedative and relaxing properties (e.g. kratom). Few information is available in relation to the analytical identification of psychoactive principles contained in the plant material. Moreover, to our knowledge, scarce data are present in literature, about the characterization and quantification of the parent drug in biological matrices from intoxication and fatality cases. In addition, the metabolism of natural active principles has not been yet fully investigated for most of the psychoactive substances from plant material. Consequently, their identification is not frequently performed and produced metabolites are often unknown. To fill this gap, we reviewed the currently available analytical methodologies for the identification and quantification of NPS of natural origin in plant material and, whenever possible, in conventional and non-conventional biological matrices of intoxicated and dead subjects. The psychoactive principles contained in the following plants were investigated: Areca catechu, Argyreia nervosa, Ayahuasca, Catha edulis, Ipomoea violacea, Mandragora officinarum, Mitragyna speciosa, Pausinystalia yohimbe, Piper methisticum, Psilocybe, Rivea corymbosa, Salvia divinorum, Sceletium tortuosum, Lactuca virosa. From the results obtained, it can be evidenced that although several analytical methods for the simultaneous quantification of different molecules from the same plants have been developed and validated, a comprehensive method to detect active compounds from different natural specimens both in biological and non-biological matrices is still lacking.

Cross-reactivity of the CEDIA buprenorphine assay with opiates: an Austrian phenomenon?

When testing the Microgenics CEDIA assay for immunological buprenorphine analysis, cross-reactivity between the buprenorphine reagents and opiates was observed at concentrations higher than 120 mg/l morphine, 320 mg/l methadone, 30 mg/l codeine, 60 mg/l dihydrocodeine and 520 mg/l morphine-3-glucuronide. The cross-reactivity with morphine has the greatest impact on routine screening as opiate maintenance therapy in Austria is also performed with slow-release oral morphine. The use of a second cutoff value of 30 mug/l for urine samples that are (immunologically) positive for opiates is therefore suggested, compared to the cutoff value of 5 microg/l proposed by the manufacturer.