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Updated: Jun 24, 2026
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A Package of Established Analytical Tools to Investigate the Solid-State Alteration of Lipid-Based Excipients
Published on: August 9, 2022
Tailor-made dissolution profiles by extruded matrices based on lipid polyethylene glycol mixtures
Maike Windbergs1, Clare J Strachan, Peter Kleinebudde
1Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-University, 40225 Düsseldorf, Germany.
Summary
This study developed stable drug delivery systems using tripalmitin and polyethylene glycol extrudates. Varying matrix composition tailored theophylline anhydrate release profiles, demonstrating controlled drug delivery potential.
Area of Science:
- Pharmaceutical Technology
- Materials Science
- Drug Delivery Systems
Background:
- Lipid-based drug delivery systems can face challenges with polymorphic transitions affecting stability and drug release.
- Controlling drug release profiles is crucial for effective therapeutic outcomes.
- Extrusion is a viable manufacturing process for creating solid dosage forms.
Purpose of the Study:
- To create tailored dissolution profiles for theophylline anhydrate using tripalmitin and polyethylene glycol extrudates.
- To investigate the solid-state stability of these extrudates under accelerated conditions.
- To evaluate the impact of polyethylene glycol on drug release mechanisms.
Main Methods:
- Production of extrudates using tripalmitin and polyethylene glycol at various ratios below their melting points.
- Characterization of drug release profiles for theophylline anhydrate by adjusting matrix composition.
- Assessment of solid-state stability through polymorphic analysis and accelerated stability testing (40°C/75% RH) for one year.
Main Results:
- Tailor-made dissolution profiles for theophylline anhydrate were achieved by modifying the matrix composition.
- The hydrophilic polymer polyethylene glycol enhanced drug dissolution by forming an interconnected pore network.
- Extrudates exhibited stable solid-state behavior with no polymorphic transformations observed post-extrusion.
- Formulations remained stable throughout the one-year accelerated stability testing.
Conclusions:
- Extrusion of tripalmitin and polyethylene glycol offers a robust method for developing stable drug delivery systems.
- Polyethylene glycol plays a key role in modulating drug release through pore network formation.
- The developed extrudates demonstrate excellent physical and chemical stability, suitable for pharmaceutical applications.
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