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Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Modeling microstructure development and release kinetics in controlled drug release coatings.
David M Saylor1, Chang-Soo Kim, Dinesh V Patwardhan
1Food and Drug Administration, Center for Devices and Radiological Health, Office of Science and Engineering Laboratories, Silver Spring, Maryland 20903, USA. david.saylor@fda.hhs.gov
Journal of Pharmaceutical Sciences
|May 16, 2008
Summary
Controlled release coatings show improved drug delivery with tailored microstructures. Understanding drug-polymer interactions is key to optimizing drug release profiles for medical devices.
Area of Science:
- Materials Science
- Biomedical Engineering
- Chemical Engineering
Background:
- Controlled release coatings, drug-polymer composites, enhance medical device performance.
- Established relationships between material properties, manufacturing, microstructure, and release kinetics are lacking.
Purpose of the Study:
- To investigate how drug-polymer chemistry, loading, and evaporation rates influence microstructure development.
- To compute drug release profiles in different media based on developed microstructures.
Main Methods:
- Application of a thermodynamically consistent model to simulate microstructure formation.
- Computation of drug release profiles under varying conditions (polymer-insoluble and polymer-soluble media).
Main Results:
- Increasing drug-polymer phobicity promotes structural heterogeneity formation at lower drug loadings and faster rates.
- Heterogeneities transition from isolated to interconnected structures with increasing drug-polymer ratios.
- Heterogeneities significantly enhance drug release in polymer-insoluble media (up to fourfold increase) but diminish it in polymer-soluble media.
Conclusions:
- Microstructure significantly impacts drug release kinetics, with effects dependent on the surrounding medium.
- Tailoring physico-chemical properties and microstructure is crucial for predictable controlled release systems.
- This approach can lead to drug release responses that are robust against manufacturing variations.
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