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Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles
Published on: August 28, 2015
Verapamil hydrochloride release characteristics from new copolymer zwitterionic matrix tablets
Bistra Kostova1, Elena Kamenska, Ivo Ivanov
1Faculty of Pharmacy, Department of Pharmaceutical Technology and Biopharmacy, Medical University, Sofia, Bulgaria.
Pharmaceutical Development and Technology
|July 24, 2008
Summary
Researchers synthesized novel zwitterionic copolymers for controlled drug release. They explained the "overshooting" phenomenon in swelling kinetics, linking it to copolymer self-association and release profiles.
Area of Science:
- Polymer Chemistry
- Materials Science
- Drug Delivery Systems
Background:
- Zwitterionic polymers offer unique properties for biomedical applications.
- Understanding swelling kinetics is crucial for controlled drug release.
- Emulsifier-free emulsion copolymerization enables synthesis of stable latexes.
Purpose of the Study:
- To synthesize stable zwitterionic latex copolymers with varying compositions.
- To elucidate the relationship between "overshooting" swelling kinetics and copolymer self-association.
- To investigate the influence of monomer composition, pH, and ionic strength on swelling and drug release.
Main Methods:
- Emulsifier-free emulsion copolymerization of vinyl acetate and a zwitterionic monomer.
- Characterization of copolymer composition and latex stability.
- Analysis of swelling kinetics and verapamil hydrochloride release from model tablets.
Main Results:
- Stable zwitterionic latex copolymers were successfully synthesized.
- A mechanism explaining the "overshooting" phenomenon in swelling kinetics was proposed, linked to copolymer self-association.
- Key parameters like monomer mole fraction, pH, and ionic strength were shown to affect swelling and drug release.
Conclusions:
- The study provides novel zwitterionic copolymers with tunable properties for drug delivery.
- The proposed mechanism enhances understanding of swelling behavior in zwitterionic systems.
- These findings are valuable for designing advanced drug delivery systems with controlled release profiles.
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