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Recrystallization of commercial carbamazepine samples-a strategy to control dissolution variability
Felicia Flicker1, Veronika A Eberle, Gabriele Betz
1Industrial Pharmacy Lab, University of Basel, Mülhauserstrasse 51, Basel 4056, Switzerland. gabriele.betz@unibas.ch.
Recrystallization of carbamazepine (CBZ) with PVP reduced dissolution variability and inhibited dihydrate formation. A subsequent controlled grinding step is crucial for consistent drug release and bioequivalence.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
Background:
- Commercial carbamazepine (CBZ) physical properties impact drug release and bioequivalence.
- Variability in CBZ samples necessitates strategies for improved consistency.
Purpose of the Study:
- To reduce variability in commercial CBZ samples through recrystallization.
- To investigate the effect of recrystallization with polyvinylpyrrolidone (PVP) on CBZ properties and dissolution.
Main Methods:
- Recrystallization of CBZ from ethanol with 1% PVP.
- Analysis using disk intrinsic dissolution rate (DIDR), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM).
Main Results:
- Recrystallized CBZ exhibited significantly reduced DIDR variability.
- Recrystallization inhibited the transformation to CBZ dihydrate.
- Inhomogenous particle size in recrystallized CBZ affected drug release in binary mixtures.
Conclusions:
- Recrystallization with 1% PVP effectively reduces CBZ dissolution variability and prevents dihydrate formation.
- A controlled grinding step post-recrystallization is essential for achieving consistent particle size and drug release.
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