Quantification of psilocin in human whole blood using liquid chromatography–tandem mass spectrometry (LC–MS/MS)

Psilocybin, a prodrug found in magic mushrooms, is converted in the body to psilocin, the compound responsible for cognitive effects. Existing methods to measure psilocin in plasma, serum, or urine may yield misleading pharmacokinetic data because the blood-to-plasma ratio is unknown. This work developed the first analytical method using solid-phase extraction and liquid chromatography–tandem mass spectrometry to quantify psilocin in human whole blood. The procedure achieved high recovery (≥89%) with minimal matrix effects, validated per ANSI/ASB 036 guidelines. Linearity ranged from 0.7 to 200 ng/mL, covering previously reported plasma levels. Psilocin was stable at 4°C for 48 hours. The method successfully detected and quantified psilocin at low limits in whole blood, though a proof-of-concept study is still needed.

Study at a glance

Abstract

Abstract There has been burgeoning interest in psilocybin‐use for the treatment of various neurological and neurodegenerative diseases. Psilocybin is mistakenly perceived as the principal pharmacologically active compound due to its high concentrations found in magic mushrooms; however, it is the prodrug of psilocin. Despite the expanding body of clinical research seeking to understand the pharmacodynamic/pharmacokinetic properties of psilocin, and its role in inducing dramatic changes to cognitive function, there has not been a corresponding increase in the development of sensitive analytical methods that can quantify psilocin in different biological fluids. Existing analytical methods have been developed using plasma, serum, and urine as the matrix of choice, but with the unknown blood‐to‐plasma ratio of psilocin, any pharmacokinetic conclusions drawn solely on plasma data may be misleading. Thus, the main objective of this study is to develop the first analytical method that utilizes SPE and LC–MS/MS to quantify psilocin in human whole blood. The SPE procedure yielded a high recovery efficiency (≥89%) with minimal matrix effects. The method was validated according to ANSI/ASB 036 guidelines. Linearity was between 0.7–200 ng/mL and encompassed previously reported ranges found in plasma/serum. Bias, within‐ and between‐run precision for all quality controls met ANSI/ASB 036 acceptability criteria. Endogenous/exogenous interferences and carryover were negligible. Psilocin stability was assessed at 4°C over 48 h and was considered stable. Although a proof‐of‐concept study will need to be performed to characterize the method, this analytical workflow was able to detect and quantify psilocin in human whole blood at low limits of quantification.