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Updated: Jun 19, 2026

Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
The binary phase diagram of propranolol hydrochloride and crystallization-based enantioseparation
Daniel Polenske1, Heike Lorenz, Andreas Seidel-Morgenstern
1Max-Planck-Institut für Dynamik komplexer technischer Systeme, Magdeburg, Germany.
Abstract:
Inconsistent results were reported for the solid-state nature of the racemic species of the pharmaceutical relevant compound propranolol hydrochloride. In this work the binary phase diagram of the propranolol hydrochloride enantiomers is studied. Differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and high performance liquid chromatography (HPLC) were used as analytical methods. The type of the racemic species, the presence and extent of partial solid solutions and the stability regions of polymorphic forms in the system were investigated. The identified binary phase diagram is sketched. Finally, the feasibility of crystallization-based resolution is discussed.
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