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Understanding biorelevant drug release from a novel thermoplastic capsule by considering microstructural formulation
Zdravka Misic1, Raphael Urbani, Thomas Pfohl
1Institute of Pharma Technology, University of Applied Sciences and Arts Northwestern Switzerland,, Gründenstr. 40, 4132, Muttenz, Switzerland.
Pharmaceutical Research
|August 8, 2013
Summary
Novel starch-based polyvinyl alcohol capsules (S-PVA-C) show partial opening in biorelevant media, leading to short lag times for fenofibrate but sustained release for probucol formulations due to hydration-induced viscosity changes.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
- Drug Delivery
Background:
- Capsule shell material significantly influences drug release profiles.
- Understanding capsule hydration and microstructural changes is crucial for predicting drug release.
Purpose of the Study:
- To investigate the biorelevant drug release from novel starch-based polyvinyl alcohol capsules (S-PVA-C).
- To evaluate the impact of shell material microstructure on drug release during hydration.
Main Methods:
- Drug release studies using a BioDis® apparatus with fenofibrate and probucol formulations.
- Capsule disintegration analysis via texture analysis.
- Microstructural analysis of hydrated capsules using small-angle X-ray scattering (SAXS).
- Comparison with gelatin (SGC) and starch (VegaGels®) capsules.
Main Results:
- S-PVA-C exhibited partial opening in biorelevant media, unlike SGC and VegaGels®.
- Fenofibrate formulation in S-PVA-C showed a short lag time, while probucol formulation demonstrated sustained release.
- Hydration of probucol formulation in S-PVA-C led to increased viscosity, impacting release, a phenomenon less pronounced in SGC and VegaGels®.
- SAXS revealed distinct hydrated microstructures.
Conclusions:
- S-PVA-C are suitable for hydrophilic formulations requiring immediate release, but careful consideration is needed.
- The hydration behavior of the drug formulation is a critical factor in selecting appropriate capsule materials for controlled release.
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