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Updated: Nov 21, 2025
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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
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New side chain design for pH-responsive block copolymers for drug delivery
Priyanka Ray1, Narendra Kale1, Mohiuddin Quadir1
1Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, ND, 58108, USA.
Colloids and Surfaces. B, Biointerfaces
|January 17, 2021
Summary
New pH-sensitive block copolymers with AZB or Ile side chains form stable nanoparticles for drug delivery. These nanocarriers effectively encapsulate and release gemcitabine, showing promise for pancreatic cancer treatment with minimal toxicity.
Area of Science:
- Polymer Chemistry
- Materials Science
- Nanotechnology
Background:
- Amphiphilic block copolymers are crucial for drug delivery systems.
- pH-sensitive polymers offer controlled drug release mechanisms.
- Developing novel pH-responsive motifs is key to enhancing nanocarrier performance.
Purpose of the Study:
- To design and investigate new molecular motifs for pH-regulating amphiphilic block copolymers.
- To enhance self-assembly properties, drug encapsulation, and release kinetics.
- To evaluate the potential of these novel nanocarriers for pancreatic ductal adenocarcinoma (PDAC) treatment.
Main Methods:
- Synthesized poly(ethylene glycol)-block-poly(carbonate) (PEG-b-PC) copolymers with appended 4-Amino-4'-dimethylaminoazobenzene (AZB) or isoleucine (Ile) side chains.
- Characterized self-assembled nanoparticles using dynamic light scattering to determine hydrodynamic diameter and critical aggregation concentration (CAC).
- Assessed gemcitabine (GEM) encapsulation efficiency, pH-dependent drug release, in vitro cellular uptake, and cytotoxicity in PDAC cells.
Main Results:
- PEG-b-PC copolymers with AZB or Ile side chains formed stable spherical nanoparticles (114-137 nm).
- CAC was influenced by the type and content of appended side chains.
- GEM-loaded nanocarriers demonstrated pH-dependent release (13.8-28.8% loading) and exhibited cytotoxicity against PDAC cells.
- No significant cytotoxicity was observed for the block copolymers or nanoparticles at effective concentrations.
Conclusions:
- AZB and Ile motifs effectively regulate pH-sensitivity in block copolymers for nanoparticle formation.
- These engineered nanocarriers show significant potential for targeted drug delivery and cancer therapy.
- The developed materials represent a promising platform for stimuli-responsive nanosystems in pharmaceutical applications.
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