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Updated: May 24, 2026
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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
Poly(L-lysine)-based star-block copolymers as pH-responsive nanocarriers for anionic drugs
Yunsong Yan1, Jiayan Li, Jinhong Zheng
1Medical College, Shantou University, 22 Xinling Road, Shantou 515041, PR China.
Colloids and Surfaces. B, Biointerfaces
|March 20, 2012
Summary
New star-block copolymers, polyethylenimine-g-(poly(l-lysine)-b-poly(ethylene glycol)) (PEI-g-(PLL-b-PEG)), efficiently encapsulate anionic drugs. These nanocarriers show pH-responsive release, offering potential for controlled drug delivery systems.
Area of Science:
- Polymer Chemistry
- Nanotechnology
- Drug Delivery
Background:
- Developing effective nanocarriers is crucial for targeted and controlled drug delivery.
- Star-block copolymers offer unique structural advantages for encapsulating therapeutic agents.
Purpose of the Study:
- To synthesize and characterize novel star-block copolymers, PEI-g-(PLL-b-PEG), as potential nanocarriers for anionic drugs.
- To evaluate the encapsulation efficiency and pH-responsive release properties of these copolymers.
Main Methods:
- Synthesis via ring-opening polymerization and surface modification.
- Characterization using 1H NMR, GPC, and DLS.
- Encapsulation and release studies using spectrophotometric titration and dialysis.
Main Results:
- Successfully synthesized PEI-g-(PLL-b-PEG) star-block copolymers.
- Demonstrated efficient encapsulation of anionic model dyes and diclofenac sodium at physiological pH.
- Observed sustained release at physiological pH and accelerated release at pH extremes (2.0-3.0 and 10.0-11.0).
Conclusions:
- PEI-g-(PLL-b-PEG) star-block copolymers are effective nanocarriers for anionic compounds.
- The pH-responsive release mechanism holds promise for controlled anionic drug delivery.
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