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Particle-Size-Determined Crystallization and Dissolution Behavior of Amorphous Griseofulvin.
Daniela Košťálová1, Roman Svoboda2, Kateřina Kozlová2
1Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, 532 10, Pardubice, Czech Republic. daniela.kostalova@upce.cz.
Pharmaceutical Research
|December 10, 2025
Summary
Particle size significantly impacts griseofulvin dissolution kinetics, offering a controllable alternative to amorphization for fine-tuning drug release. Coarse amorphous griseofulvin powders provide delayed dissolution, negating the need for amorphization for enhanced bioavailability.
Area of Science:
- Pharmaceutical Science
- Materials Science
Background:
- Amorphous active pharmaceutical ingredients (APIs) generally exhibit higher bioavailability than crystalline forms due to enhanced solubility.
- Particle size of powdered APIs can influence properties similarly to amorphous states.
Purpose of the Study:
- To investigate the particle-size-influenced properties of amorphous griseofulvin powders.
- To compare the dissolution profiles of amorphous and crystalline griseofulvin in pharmaceutical tablets.
Main Methods:
- Calorimetric, spectroscopic, and microscopic studies of amorphous griseofulvin crystallization (20-1000 μm).
- Dissolution profile analysis of pharmaceutical tablets containing different griseofulvin powder fractions under simulated gastrointestinal conditions.
Main Results:
- A rapid diffusionless growth mode was observed for the finest griseofulvin powders at low heating rates.
- Dissolution profiles followed the Korsmeyer-Peppas model, indicating super case II transport release mechanisms.
Conclusions:
- Particle size plays a dominant role in griseofulvin dissolution kinetics, overshadowing differences between amorphous and crystalline states.
- Coarse amorphous griseofulvin powders offer controlled, delayed dissolution, providing a viable alternative to amorphization for tuning drug release profiles.
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