Cyclodextrin-Responsive Micelles Based on Poly(ethylene glycol)-Polypeptide Hybrid Copolymers as Drug Carriers

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Nanotechnology

Background:

• Development of advanced drug delivery systems is crucial for targeted and efficient therapeutic interventions.
• Polymeric micelles offer a promising platform for encapsulating and delivering hydrophobic drugs.
• Stimuli-responsive materials enhance drug release control and therapeutic efficacy.

Purpose of the Study:

• To synthesize and characterize novel four-armed poly(ethylene glycol)-polypeptide copolymers.
• To investigate the self-assembly of these copolymers into core-shell micelles in aqueous solutions.
• To evaluate the triggered disassembly of micelles and drug release in response to beta-cyclodextrin.

Main Methods:

• Ring-opening polymerization of amino acid N-carboxyanhydrides to synthesize copolymers.
• Micelle formation in aqueous solutions and characterization.
• In vitro drug release studies using doxorubicin (DOX) and beta-cyclodextrin (β-CD).
• Cytotoxicity and cell internalization assays.

Main Results:

• Successfully synthesized poly(ε-adamantane-l-lysine)2-block-poly(ethylene glycol)-block-poly(ε-adamantane-l-lysine)2 (PLys(Ad)2-b-PEG-b-PLys(Ad)2) copolymers.
• Copolymers spontaneously formed stable core-shell micelles in aqueous media.
• Micelles demonstrated triggered disassembly and accelerated release of doxorubicin upon addition of beta-cyclodextrin.
• Investigated cytotoxicity and cellular uptake of the drug-loaded micelles.

Conclusions:

• Novel PEG-polypeptide copolymers form stimuli-responsive micelles suitable for drug delivery.
• Beta-cyclodextrin effectively triggers micelle disassembly and enhances drug release.
• These micelles exhibit potential for controlled and targeted doxorubicin delivery applications.