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Microwave-assisted Functionalization of Poly(ethylene glycol) and On-resin Peptides for Use in Chain Polymerizations and Hydrogel Formation
Published on: October 29, 2013
Cyclodextrin/poly(ethylene glycol) polypseudorotaxane hydrogels as a promising sustained-release system for lysozyme
Taishi Higashi1, Anna Tajima, Keiichi Motoyama
1Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 862-0973, Japan.
Journal of Pharmaceutical Sciences
|June 9, 2012
Summary
Polypseudorotaxane (PPRX) hydrogels made with poly(ethylene glycol) (PEG) and cyclodextrins (CyD) effectively sustained lysozyme release. These hydrogels show promise for protein drug delivery systems.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Polymer Chemistry
Background:
- Protein-based therapeutics require advanced delivery systems for sustained release.
- Polypseudorotaxane (PPRX) hydrogels offer potential for controlled drug delivery.
- Poly(ethylene glycol) (PEG) and cyclodextrins (CyD) are key components in PPRX hydrogel formation.
Purpose of the Study:
- To evaluate the utility of cyclodextrin (CyD) polypseudorotaxane (PPRX) hydrogels for sustained protein drug release.
- To investigate the release profiles and mechanisms of lysozyme from α- and γ-CyD PPRX hydrogels.
Main Methods:
- Preparation of CyD PPRX hydrogels incorporating lysozyme.
- In vitro release studies of lysozyme from the hydrogels.
- Analysis of release kinetics using the Korsmeyer-Peppas model.
Main Results:
- Lysozyme encapsulation significantly decreased in vitro release rates.
- α- and γ-CyD formed PPRX hydrogels via physical cross-linking of PEG chains.
- Release mechanisms from both α- and γ-CyD systems were statistically similar, indicating consistent behavior.
Conclusions:
- α- and γ-CyD PPRX hydrogels demonstrate potential as effective sustained-release systems for protein drugs like lysozyme.
- The physical cross-linking mechanism provides a basis for controlled protein release.
- Further development of CyD PPRX hydrogels could advance protein drug delivery technologies.
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