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Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
PEG-stabilized micellar system with positively charged polyester core for fast pH-responsive drug release
Hua-Fen Wang1, Hui-Zhen Jia, Si-Xue Cheng
1Key Laboratory of Biomedical Polymers, The Ministry of Education, Department of Chemistry, Wuhan University, Wuhan, 430072, China.
Pharmaceutical Research
|January 25, 2012
Summary
Functional drug carriers were developed for rapid pH-responsive drug release. These PEGylated terpolymers self-assemble into stable micelles, demonstrating accelerated drug release in acidic conditions for improved therapeutic delivery.
Area of Science:
- Polymer Chemistry
- Nanotechnology
- Drug Delivery Systems
Background:
- Development of advanced drug carriers is crucial for targeted and efficient therapeutic delivery.
- pH-responsive materials offer potential for controlled drug release in specific physiological environments.
- Polymeric micelles provide a versatile platform for encapsulating and delivering hydrophobic drugs.
Purpose of the Study:
- To design functional drug carriers capable of rapid pH-responsive drug release.
- To synthesize and characterize novel PEGylated terpolymers for drug delivery applications.
- To investigate the self-assembly behavior and pH-dependent drug release kinetics of the developed carriers.
Main Methods:
- Fabrication of functional diblock terpolymers: monomethoxy poly(ethylene glycol)-block-copoly(6,14-dimethyl-1,3,9,11-tetraoxa-6,14-diaza-cyclohexadecane-2,10-dione-co-ε-caprolactone) [mPEG-b-poly(ADMC-co-CL)] via biosynthetic pathway.
- Preparation of self-assembled nanospheres and drug-loaded micelles using the dialysis method.
- Evaluation of pH-tunable morphology variations and drug release patterns at different pH levels.
Main Results:
- Three PEGylated terpolymers with varying compositions exhibited high cell-biocompatibility.
- Copolymers self-assembled into stable nanoscale micelles (~100 nm) in aqueous media, maintaining integrity over 80-hour incubation.
- Acid-induced structural deformation of micelles was observed due to protonation-deprotonation of tertiary amine groups, leading to remarkably accelerated drug release (e.g., ibuprofen) in acidic conditions.
Conclusions:
- Functional PEG-stabilized micellar carriers with a positively charged polyester core were successfully developed.
- The developed micellar systems demonstrate fast pH-responsive drug release capabilities.
- These carriers hold promise for advanced drug delivery applications requiring triggered release in acidic environments.
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