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Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
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Unlocking the potential of alkaline polymethacrylates via ionic crosslinking in amorphous solid dispersions
Lukas Mild1, Alicia Stakemeier1, My Ngoc Nguyen Thi2
1Department of Pharmaceutical Technology and Biopharmaceutics, University of Bonn, Gerhard-Domagk-Strasse 3, 53121 Bonn, Germany.
International Journal of Pharmaceutics: X
|April 21, 2026
Summary
Acid-modified alkaline polymethacrylates create stable amorphous solid dispersions (ASDs) for poorly soluble drugs. This novel approach enhances oral bioavailability by controlling polymer protonation for improved drug release and performance.
Area of Science:
- Pharmaceutical Sciences
- Materials Science
Background:
- Amorphous solid dispersions (ASDs) improve oral bioavailability of poorly water-soluble drugs.
- Challenges include drug-polymer compatibility and pH-dependent performance.
Purpose of the Study:
- Investigate alkaline polymethacrylates (Eudragit® E) as carriers for ASDs.
- Develop acid-modified formulations for enhanced performance under physiological conditions.
Main Methods:
- Prepared ASDs using hot-melt extrusion (HME) and vacuum compression molding (VCM).
- Characterized drug-polymer miscibility, thermal behavior, and dissolution.
- Assessed stability under various storage conditions.
Main Results:
- Confirmed complete amorphization and stable glass formation.
- Acid modification induced controlled polymer protonation and ionic crosslinking.
- Achieved rapid and sustained drug supersaturation at pH 6.8, exceeding drug solubility.
- Dissolution performance correlated with polymer protonation degree.
Conclusions:
- Acid-modified alkaline polymethacrylates offer a versatile platform for ASD formulation.
- Decouples solubility enhancement from drug chemistry via polymer-driven ionic crosslinking.
- Enables rational development of stable, high-performance formulations for poorly water-soluble drugs.
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