(235g) Tunable Molecular Self-Assembly of Dynamic Oligopeptide Materials

High aspect-ratio nanostructures prepared through the self-assembly of oligopeptides has been a versatile strategy to create functional soft materials. In particular, the assembly of very short peptides has attracted interest in efforts to achieve maximal function with minimal material. Yet, such assemblies are often best described in phenomenological terms. We have explored a series of aromatic tripeptides to generate a variety of nanostructures that are dependent on sequence, and further uncover the design rules governing assembly of these short peptides. In addition, we evaluated the attachment of short peptide grafts to aromatic discotic or metal-chelating prosthetic groups to achieve materials with assembly governed by their peptide substituents in concert with non-peptidic recognition motifs. This combination of interactions furthermore leads to interesting pathway dependence in the final assembly, yielding hierarchical structural organization across length-scales. Finally, we demonstrated the formation of transient self-assemblies where nanostructure formation and lifetime are dictated by the presence and concentration of a metabolite “fuel” feed. In sum, the diversity afforded from facile creation of minimal and discrete small molecules based on peptides and aromatics, combined with attention to the thermodynamic pathway of assembly, leads to a diversity of nanostructures and materials with tunable and controllable properties across the nano- to mesoscale.