The self-assembly of cystine-bridged γ-peptide-based cyclic peptide-dendron hybrids

Novel cystine-bridged γ-peptide-based cyclic peptide-dendron hybrids have been synthesized by oxidative coupling between two cysteine residues of the linear peptides via the formation of disulfide bonds in high yields. The self-assembly of the hybrids was studied by FT-IR, (1)H NMR, TEM, and AFM analyses which indicate that the nanotube was constructed through intermolecular hydrogen-bonding of the hydrophobic cyclic peptide moieties and possesses amphiphilic property by conjugating a hydrophilic dendron on the exterior of the cyclic peptide ring. The diameters of nanofibers that consisted of nanotubes depend on the employed solvent in the self-assembly process, and uniform filaments formed from double amphiphilic nanotubes via hydrophobic interactions between their hydrophobic faces have been observed in water as well as in aqueous solutions.