Geometrical Shape of Hydrophobic Section Determines the Self-Assembling Structure of Peptide Detergents and Bolaamphiphilic Peptides

Geometrical compatibility is a very important factor for molecular self-assembly. In the self-assembling systems of peptide detergents and bolaamphiphilic peptides, the effect of the geometrical shape of hydrophobic section on the self-assembling behavior has been investigated by nanostructure characterization. It is shown that in aqueous solutions of both peptide detergent and bolaamphiphilic peptide systems, peptides bearing hydrophobic sections with constant size tend to form discrete structures including nanofibers, nanorods and nanospheres, while peptides bearing wedge-shaped hydrophobic sections tend to form haploid long nanofibers. And a peptide detergent with inverted-wedged hydrophobic tail tends to form reversed micelle in nonpolar solvent environment. These results indicate that the self-assembling behavior of peptide amphiphiles could be rationally controlled by the geometrical shape of the hydrophobic section, suggesting a novel strategy for fabricating controllable nanostructures. Keywords: Geometrical compatibility, Self-assembly, Peptide detergent, Bolaamphiphilic peptide, Hydrophobic section