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Solid-phase Submonomer Synthesis of Peptoid Polymers and their Self-Assembly into Highly-Ordered Nanosheets
Published on: November 2, 2011
Vesicles from peptidic side-chain polymers synthesized by atom transfer radical polymerization
Dave J Adams1, Derek Atkins, Andrew I Cooper
1Unilever Corporate Research, Sharnbrook, Bedford, MK44 1LQ, United Kingdom. d.j.adams@liverpool.ac.uk
Biomacromolecules
|September 30, 2008
Summary
Researchers synthesized novel peptide-polymer block copolymers that self-assemble into vesicles. These self-assembling block copolymers show potential for various applications, with some forming unique toroidal structures.
Area of Science:
- Polymer Chemistry
- Supramolecular Chemistry
- Biomaterials Science
Background:
- Block copolymers are known to form diverse morphologies in aqueous solutions.
- Block copolymer vesicles are of significant interest for numerous applications.
- Developing novel self-assembling materials with tunable properties is crucial.
Purpose of the Study:
- To synthesize and characterize novel poly(ethylene oxide)-b-poly(side-chain peptides) block copolymers.
- To investigate the self-assembly behavior of these copolymers in aqueous solutions.
- To explore the potential of these materials for forming vesicular structures.
Main Methods:
- Peptide synthesis using conventional coupling techniques.
- Polymerization via atom transfer radical polymerization (ATRP) in hexafluoroisopropanol (HFIP).
- Self-assembly induced by organic to aqueous solvent exchange.
- Morphological characterization using techniques like circular dichroism.
Main Results:
- Successfully synthesized poly(ethylene oxide)-b-poly(side-chain peptides) with oligo(valine) and oligo(phenylalanine) blocks.
- Demonstrated self-assembly into vesicles upon solvent exchange for many synthesized polymers.
- Observed formation of toroids and vesicles for a divaline hydrophobic block example.
- Circular dichroism confirmed secondary structure formation within the vesicle walls for valine-containing polymers.
Conclusions:
- Novel peptide-polymer block copolymers can be synthesized using ATRP.
- These copolymers effectively self-assemble into vesicles and other morphologies.
- The self-assembled structures exhibit secondary ordering, indicating potential for functional biomaterials.
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