Self-Assembly of Surfactant-like Peptides

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Self-Assembly of Surfactant-like Peptides
Steve S. Santoso, Sylvain Vauthey Shuguang
Zhang Center for Biomedical Engineering Massachuse
tts Institute of Technology
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Nanostructures

• Structures ranging from 1 to 100 nm
• Sub-micrometer science and engineering that
  combine multiple disciplines
• Chemistry
• Biology
• Physics
• Material science
• Engineering
• How to build / design nanostructures?
• Want the atomic selectivity of synthetic
  chemistry yet the expandability of engineering
• Molecular self-assembly may be useful

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• Self-assembly processes common in biological
  systems
• Cell membrane
• Multi-component cellular machinery ribosome
• Protein folding

• Self-assembly involves non-covalent bonding
• van der Waals
• hydrogen bonds
• dipolar forces
• dynamic process

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Surfactant-like peptides
Ac-VVVVVVD
Six hydrophobic valines (tail) One polar aspartic
acid (head)
2 nm
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Preliminary experiments and results

• Some condition screening
• Use dynamic light scattering (DLS), TEM
• Found larger structures for some conditions

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Cryo-TEM
300 nm
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Nanotubes are not the structure with energetic
global minimum
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Nanovesicle
RF

• Controlled delivery of small chemicals
• Use nanovesicle to study replication of
  biological
• materials in an enclosed environment

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150 nm
550 nm
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• Summary
• Peptide surfactants are promising substrates
  for advanced
• material and its application.
• Cost-effective
• Certain structures will form under certain
  environmental
• and chemical conditions
• Tunable

• Biological origin may be advantageous for
  medical application
• A good system to study self-assembly.