Synthesis of a Stable Helical Peptide and Grafting on Gold Nanoparticles

A N-(8-mercaptooctanoyl)heptapeptide, comprising six CĄ-tetrasubstituted amino acids and a C-terminal histidine residue, has been synthesized by solution methods. The preferred conformation of this peptide and its hexapeptide precursor is that of a 310-helix. Gold nanoparticles have been functionalized with the peptide-thiol by place exchange reaction and the spectroscopic data indicate that the helical conformation of the peptide is maintained in the aggregate. The material obtained may constitute a synthetic model of a globular protein.