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Glucose-responsive vehicles containing phenylborate ester for controlled insulin release at neutral pH
Yuan Yao1, Liyuan Zhao, Junjiao Yang
1State Key Laboratory of Chemical Resource, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
Biomacromolecules
|April 28, 2012
Summary
Researchers developed glucose-sensitive nanoparticles using amphiphilic block polymers for drug delivery. These phenylborate ester-based micelles show potential for self-regulated insulin delivery with low toxicity.
Area of Science:
- Polymer Chemistry
- Materials Science
- Nanotechnology
Background:
- Developing effective drug delivery systems is crucial for targeted therapies.
- Glucose-responsive materials offer potential for self-regulated drug release, particularly for diabetes management.
Purpose of the Study:
- To synthesize and characterize amphiphilic block polymers for glucose-sensitive nanoparticle formation.
- To evaluate the potential of these nanoparticles as a drug carrier for insulin delivery.
Main Methods:
- Atom transfer radical polymerization (ATRP) to synthesize poly(ethylene glycol)-block-poly[(2-phenylboronic esters-1,3-dioxane-5-ethyl) methylacrylate] (MPEG5000-block-PBDEMA).
- Solvent evaporation method for self-assembly into core-shell micelles.
- Zeta potential, fluorescence spectroscopy, in vitro release studies, circular dichroism, 1H NMR, and cell viability assays.
Main Results:
- Successfully synthesized MPEG5000-block-PBDEMA that self-assembled into micelles.
- Achieved high encapsulation efficiency and loading capacity for FITC-insulin.
- Demonstrated significant glucose-responsive insulin release at physiological conditions (pH 7.4, 37 °C).
- Confirmed structural integrity of released insulin and low cytotoxicity of the nanoparticles.
Conclusions:
- The developed phenylborate ester-containing block polymers form glucose-sensitive micelles suitable for drug delivery.
- These nanoparticles exhibit potential for self-regulated insulin delivery systems.
- The mechanism involves a polymer polarity transition in response to glucose concentration.
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