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Thermal behaviour and dissolution properties of phenylbutazone polymorphs.
The Journal of Pharmacy and Pharmacology
|April 1, 1983
Summary
Phenylbutazone polymorphs interconvert, especially at slower heating rates or upon grinding, impacting dissolution behavior. The Berthoud model accurately describes dissolution, influenced by tablet excipients.
Area of Science:
- Pharmaceutical Sciences
- Solid-State Chemistry
Background:
- Polymorphism significantly affects drug properties like solubility and bioavailability.
- Understanding phenylbutazone's solid-state behavior is crucial for formulation development.
Purpose of the Study:
- To prepare and characterize phenylbutazone polymorphs.
- To investigate their interconversion behavior.
- To evaluate dissolution characteristics and the applicability of the Berthoud model.
Main Methods:
- Differential scanning calorimetry (D.S.C.) for thermal analysis.
- Preparation and characterization of five phenylbutazone polymorphic forms.
- Equilibrium solubility and intrinsic dissolution rate measurements.
Main Results:
- Observed interconversion of three polymorphs to a more stable form under specific conditions (slow heating, grinding).
- Dissolution process successfully modeled using the Berthoud equation.
- Identified influence of tablet excipients on dissolution.
Conclusions:
- Phenylbutazone exhibits polymorphic interconversion, affecting its solid-state properties.
- The Berthoud model is suitable for describing phenylbutazone dissolution.
- Excipients play a role in the dissolution performance of phenylbutazone formulations.
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