Surface mediated hierarchical assemblies of highly hydrophobic phenylalanine-based peptides

Abstract

We report the noticeable control exerted by the surface in the self-assembly of a highly hydrophobic triphenylalanine peptide with fluorenyl functionalities blocking the two ends. The remarkable differences observed among the polymorphic hierarchical assemblies obtained onto silanized glass, scratched glass, stainless steel, exfoliated mica, silicon wafer, carbon, polytetrafluoroethylene, plasma-functionalized, polystyrene and nitrocellulose substrates are consequence of the balance between peptide···peptide and peptide···surface interactions. This balance is greatly influenced by the surface characteristics, as defined by the wettability (hydrophobicity or hydrophilicity) and roughness (degree of flatness and regularity). Furthermore, very stable dendritic structures, in which primary frameworks nucleated from the center grow according to a 4-fold pseudo-symmetry branching, have been obtained onto hydrophilic treated polystyrene.