Self-Assembly of Surfactant-like Peptides
Steve S. Santoso, Sylvain Vauthey &
Shuguang Zhang
Center for Biomedical Engineering
Massachusetts Institute of Technology
Nanostructures
• Structures ranging from 1 to 100 nm
• Sub-micrometer science and engineering that combine
multiple disciplines:
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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
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
Surfactant-like peptides
[Ac]-VVVVVVD
Six hydrophobic valines (tail)
One polar aspartic acid (head)
2 nm
Preliminary experiments and results
• Some condition screening
• Use: dynamic light scattering (DLS), TEM
• Found larger structures for some conditions:
Cryo-TEM:
300 nm
Nanotubes are not the structure with energetic global
minimum:
Nanovesicle
RF
• Controlled delivery of small chemicals
• Use nanovesicle to study replication of biological
materials in an enclosed environment
150 nm
550 nm
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.