You cannot fight the pressure: Structural rearrangements of active pharmaceutical ingredients under magic angle spinning

Please always quote using this URN: urn:nbn:de:bvb:20-opus-318838
  • Although solid-state nuclear magnetic resonance (NMR) is a versatile analytical tool to study polymorphs and phase transitions of pharmaceutical molecules and products, this work summarizes examples of spontaneous and unexpected (and unwanted) structural rearrangements and phase transitions (amorphous-to-crystalline and crystalline-to-crystalline) under magic angle spinning (MAS) conditions, some of them clearly being due to the pressure experienced by the samples. It is widely known that such changes can often be detected by X-ray powderAlthough solid-state nuclear magnetic resonance (NMR) is a versatile analytical tool to study polymorphs and phase transitions of pharmaceutical molecules and products, this work summarizes examples of spontaneous and unexpected (and unwanted) structural rearrangements and phase transitions (amorphous-to-crystalline and crystalline-to-crystalline) under magic angle spinning (MAS) conditions, some of them clearly being due to the pressure experienced by the samples. It is widely known that such changes can often be detected by X-ray powder diffraction (XRPD); here, the capability of solid-state NMR experiments with a special focus on \(^{1}\)H-\(^{13}\)C frequency-switched Lee–Goldburg heteronuclear correlation (FSLG HETCOR)/MAS NMR experiments to detect even subtle changes on a molecular level not observable by conventional 1D NMR experiments or XRPD is presented. Furthermore, it is shown that a polymorphic impurity combined with MAS can induce a crystalline-to-crystalline phase transition. This showcases that solid-state NMR is not always noninvasive and such changes upon MAS should be considered in particular when compounds are studied over longer time spans.show moreshow less

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Metadaten
Author: Sebastian Scheidel, Laurina Östreicher, Isabelle Mark, Ann-Christin Pöppler
URN:urn:nbn:de:bvb:20-opus-318838
Document Type:Journal article
Faculties:Fakultät für Chemie und Pharmazie / Institut für Organische Chemie
Language:English
Parent Title (English):Magnetic Resonance in Chemistry
Year of Completion:2022
Volume:60
Issue:6
First Page:572
Last Page:582
Source:Magnetic Resonance in Chemistry 2022, 60(6):572-582. DOI: 10.1002/mrc.5267
DOI:https://doi.org/10.1002/mrc.5267
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 54 Chemie / 547 Organische Chemie
Tag:API; MAS; XRPD; \(^{1}\)H-\(^{13}\)C HETCOR; solid-state NMR; structural changes
Release Date:2023/08/09
Licence (German):License LogoCC BY-NC: Creative-Commons-Lizenz: Namensnennung, Nicht kommerziell 4.0 International