Assembly pathway control of programmable peptide nanomaterials and inorganic templating*

Self-assembly programmability requires specific interactions displayed at specified positions on molecules. We use computationally designed peptides with pre-determined coiled-coil conformations to precisely install local interactions through certain amino acids at certain peptide sequence positions. Primary sequences were designed based on a mathematical model of an anti-parallel, α-helical, homotetrameric coiled-coil bundle. Programmability was achieved with modification of the exterior amino acid residues in the context of desired 2D local symmetries, such as P422 or P222. These designed peptides have shown the ability to self-assemble into 2D nanomaterials. Solution temperature and pH, were explored to kinetically control the assembly process for the accelerated formation of high-quality 2D nanoplatelets; or to drive the assembly process along alternative assembly pathways creating nanomterials with different morphologies, such as nanotubes, nanoplatelets or needles. Furthermore, with modification of an extra included cysteine, these self-assembled peptide nanomaterials can be used to template the growth of gold nanoparticles into controllable organization.