Psilocybin: Characterization of the Metastable Zone Width (MSZW), Control of Anhydrous Polymorphs, and Particle Size Distribution (PSD)
Robert B. Kargbo, Alexander M. Sherwood, Poncho Meisenheimer, Kelsey Lenoch, Solomon B. Abebe
ACS Omega February 7, 2022 DOI: 10.1021/acsomega.1c06708 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Intervention | water recrystallization |
| Topics | Psilocybin |
| Keywords | Nucleation Metastability Recrystallization geology Crystallography Polymorphism computer science Particle size Particle-size distribution Crystallinity Chemical engineering Supersaturation |
| Citations | 5 |
| Key findings | A thermodynamically controlled crystallization process for psilocybin yields stronger crystal interactions, controlled particle size distribution, and improved impurity profile, with polymorph formation dependent on drying conditions. |
Abstract
Psilocybin, a serotonergic agonist, was granted a "breakthrough therapy" status by the Food and Drug Administration for clinical trials involving major depressive disorder and treatment-resistant depression. The direct phosphorylation of psilocin to psilocybin that uses a fast crystallization associated with a kinetically controlled process resulted in a smaller particle size distribution. Herein, the measurement of the metastable zone width (MSZW) and nucleation induction enabled a thermodynamically controlled crystallization process, which leads to the formation of a crystal structure with stronger interactions, controlled particle size distribution (PSD), and improved impurity profile. Employing a high-resolution inline microscopy viewer allowed the real-time monitoring of the crystallization process and the measurement of the particle size. We also present a comprehensive study of the formation of polymorph B (trihydrate), polymorph A (anhydrate), and polymorph H (anhydrate) using water recrystallization, which indicates that the formation of polymorph B (trihydrate) is independent of the crystallization method. However, polymorphs A and H are dependent on the mode of drying: drying at room temperature under vacuum gives rise to mainly polymorph A, and when heated even at relatively low temperatures, a mixture of polymorphs A and H beings to form.