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Updated: Sep 16, 2025
10:53
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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Synthesis and Characterization of Polymer-Drug Conjugates by Strain-Promoted Azide-Alkyne Cycloaddition-Mediated
Omotola D Gbadegesin1, Simeon K Adesina1
1Department of Pharmaceutical Sciences, Howard University, Washington DC, USA.
Journal of Applied Polymer Science
|July 9, 2025
Summary
We developed novel polymer-drug conjugates (PDCs) for targeted cancer therapy. This method enables efficient synthesis of high molecular weight PDCs with high drug loading for selective delivery of anticancer agents.
Area of Science:
- Polymer Chemistry
- Drug Delivery
- Nanomedicine
Background:
- Polymer-drug conjugates (PDCs) are crucial for improving the efficacy and safety of anticancer drugs by modifying their biodistribution.
- Off-target adverse effects remain a challenge with conventional small-molecule anticancer agents.
Purpose of the Study:
- To synthesize novel polymer-drug conjugates (PDCs) using a catalyst-free, high-temperature-free polymerization method.
- To achieve high molecular weight PDCs with high drug loading and narrow molecular weight distribution.
- To evaluate the drug release mechanism and potential for selective drug delivery.
Main Methods:
- Strain-promoted [3 + 2] azide-alkyne cycloaddition-mediated step-growth polymerization was employed.
- Synthesis of α-ω-bis-azide-terminated monomers coupled with gemcitabine or doxorubicin via a cathepsin B-sensitive peptide linker (GFLG).
- Polymerization with a dibenzoazacyclooctyne bifunctional polyethylene glycol monomer.
Main Results:
- Rapid synthesis of high molecular weight PDCs (gemcitabine ~40.18 kDa, doxorubicin ~1800 kDa) with narrow molecular weight distribution.
- Achieved high drug loading: 29.2% wt. gemcitabine and 10.3% wt. doxorubicin.
- Demonstrated cathepsin B-catalyzed drug release at pH 5.0 in preliminary in vitro studies.
Conclusions:
- The developed polymerization method enables efficient and selective synthesis of PDCs.
- These PDCs show potential for targeted delivery of potent anticancer agents, minimizing off-target effects.
- The study highlights a promising approach for developing advanced cancer therapeutics.
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