The Detection of Psilocin in Human Urine

Abstract

Pharmacokinetic studies of psilocybin in humans have shown the rapid dephosphorylation of psilocybin to psilocin with further conversion to 4-hydroxy-tryptophole (4HT) and 4-hydroxyindole-3-acetic acid (4HIAA) in plasma. Our study shows that psilocin also undergoes conjugation and can be found in the urine as the psilocin-glucuronide conjugate. Recoveries after enzymatic hydrolysis of the urine with β-glucuronidase (Helix Pomatia or E. Coli) when compared to non-hydrolyzed urine confirmed the presence of the glucuronide. Detection of psilocin from hydrolyzed and extracted samples was optimized for GC/MS by derivatization with MSTFA. The method developed allows for the detection of psilocin in urine with a limit of quantitation of 10 ng/mL, based on 5 mL of spiked urine. Using this method, our laboratory has confirmed the presence of psilocin in 6 out of 8 urine samples, with concentrations ranging from 10 ng/mL to greater than 200 ng/mL. Before implementation of the hydrolysis and derivatization steps, our limit of detection was 200 ng/mL, based on spiked urine standards. No case samples were positive without hydrolysis and derivatization.

Metabolism and toxicological analyses of hallucinogenic tryptamine analogues being abused in Japan

“…In 1961 and 1962, psilocybin was reported to be rapidly dephosphorylated to form psilocin by phosphatase in human bodies [10,11]. Sticht and Käferstein [12] and Grieshaber et al [13] reported the analysis of psilocin in serum and urine specimens from magic mushroom abusers. Administration experiments also showed the conversion of psilocybin into psilocin in healthy volunteers [14][15][16].…”

Champignons hallucinogènes d'Europe et des Amériques : mise au point mycologique et toxicologique

“…Elle est ensuite transformée en 4-hydroxyindole-acétaldéhyde (4-HIA) puis en acide 4-hydroxyindole-3-acétique (4-HIAA) et en 4-hydroxytryptophol (28). Le dérivé glycuroconjugué de la psilocine prédomine dans l'urine mais n'est pas toujours mis en évidence (28,39,40). Ce métabolisme est représenté sur la Figure 2.…”

“…Les méthodes utilisées sont la CLHP avec un détecteur électrochimique, sur une colonne Spherisorb RP-8 par exemple (29,41,54), mais un système REMEDi HS a déjà été utilisé avec succès pour doser la psilocine dans l'urine (39). La CG-SM après dériva-tion est très performante, avec le proadifen ou la morphine deutérée comme étalon interne (39,40,49,50 Enfin, après leur création par un descripteur initial, certaines espèces ne sont pas retrouvées avant de nombreuses années. Entre temps, elles peuvent sembler être des espèces fantômes ou les contours de leur définition peuvent devenir assez flous.…”

Development of a psilocin immunoassay for serum and blood samples

“…Therefore, it is necessary to analyse body fluids from suspected drivers to prove an abuse of drugs like psilocin. Different chromatographic methods have been described for the detection of psilocin in body fluids: REMEDi HS as a drug screening method based on HPLC [6], HPLC with electrochemical detection [5,7,8], GC-MS [6,9], liquid chromatography with APCI-MS [10] and LC-MS-MS [11]. While the determination of psilocin in urine can be performed without sample clean-up, the analysis in plasma or serum requires an extraction procedure, followed by derivatisation of the extracts in the case of GC-MS.…”