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Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Solid-state stability and characterization of hot-melt extruded poly(ethylene oxide) films
Suneela Prodduturi1, Rahul V Manek, William M Kolling
1Food and Drug Administration, Division of Pharmaceutical Analysis, St. Louis, Missouri 63101, USA.
Journal of Pharmaceutical Sciences
|September 2, 2005
Summary
Poly(ethylene oxide) (PEO) hot-melt extrusion films containing clotrimazole (CT) showed drug recrystallization after 3 months of storage. PEO is a promising drug carrier, but physical stability needs further investigation.
Area of Science:
- Materials Science
- Polymer Chemistry
- Pharmaceutical Technology
Background:
- Poly(ethylene oxide) (PEO) is a versatile polymer with potential applications in drug delivery systems.
- Hot-melt extrusion (HME) is an efficient technology for preparing polymer-drug matrices.
- Clotrimazole (CT) is an antifungal agent often formulated for topical or oral administration.
Purpose of the Study:
- To prepare and characterize thin polymer films of PEO containing clotrimazole (CT) using hot-melt extrusion (HME).
- To evaluate the solid-state properties, moisture sorption, bioadhesion, mechanical characteristics, drug release, and stability of CT within PEO films.
- To investigate the influence of PEO molecular weight on the properties and stability of the drug-loaded films.
Main Methods:
- Hot-melt extrusion (HME) was employed to fabricate PEO-CT films with two different PEO molecular weights.
- Differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) were used for solid-state characterization.
- A Texture analyzer assessed bioadhesive and mechanical properties; stability studies were conducted at 25°C/60% RH for up to 12 months.
Main Results:
- XRD analysis revealed physical instability of clotrimazole (CT), indicated by drug recrystallization after 3 months of storage at 25°C/60% RH.
- DSC studies suggested that PEO chain folding and unfolding during HME processing and storage may induce CT recrystallization.
- PEO demonstrated favorable bioadhesive, mechanical, and thermoplastic properties suitable for drug carrier applications.
Conclusions:
- PEO-based HME films show promise as drug delivery systems due to favorable material properties.
- The physical instability of clotrimazole within PEO films, evidenced by recrystallization, requires further research and optimization.
- Strategies to enhance the physical stability of PEO-CT systems are necessary for successful pharmaceutical development.
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