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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
Drug release from pH-responsive thermogelling pentablock copolymers
Michael D Determan1, James P Cox, Surya K Mallapragada
1Department of Chemical and Biological Engineering, Iowa State University and Ames Laboratory,144 Spedding Hall, Ames, Iowa 50011, USA.
Journal of Biomedical Materials Research. Part A
|November 23, 2006
Summary
This study presents a novel injectable drug delivery system using a pH-dependent pentablock copolymer. This system forms gels at body temperature, enabling sustained drug release influenced by pH.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Drug Delivery Systems
Background:
- Developing injectable sustained delivery systems is crucial for effective therapeutic administration.
- Stimuli-responsive polymers offer potential for controlled drug release.
- Cationic polymers can enhance drug solubility and interaction.
Purpose of the Study:
- To develop and characterize a novel pH-dependent injectable sustained delivery system.
- To investigate the sol-gel transition and micellization properties of a specific pentablock copolymer.
- To evaluate the drug release kinetics and pH-dependency of the developed system.
Main Methods:
- Synthesis and characterization of a cationic pentablock copolymer: PDEAEM-PEO-PPO-PEO-PDEAEM.
- Investigation of temperature and pH-dependent sol-gel transitions and micellization.
- In vitro drug release studies using model drugs and proteins at varying pH levels.
Main Results:
- The pentablock copolymer exhibits thermoreversible sol-gel transition above 37°C and pH-dependent micellization.
- Micelles formed by the copolymer enhance the solubility of hydrophobic drugs.
- Sustained zero-order drug release was observed in vitro, significantly influenced by the pH of the release media.
Conclusions:
- The developed pH-dependent injectable sustained delivery system shows promise for modulated drug delivery.
- The copolymer's ability to form gels at body temperature and control release rates makes it suitable for targeted therapies.
- This system offers a versatile platform for delivering various therapeutic agents, including proteins.
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