Nanostructured films from hierarchical self-assembly of amyloidogenic proteins.

In nature, sophisticated functional materials are created through hierarchical self-assembly of simple nanoscale motifs. In the laboratory, much progress has been made in the controlled assembly of molecules into one-, two- and three-dimensional artificial nanostructures, but bridging from the nanoscale to the macroscale to create useful macroscopic materials remains a challenge. Here we show a scalable self-assembly approach to making free-standing films from amyloid protein fibrils. The films were well ordered and highly rigid, with a Young's modulus of up to 5-7 GPa, which is comparable to the highest values for proteinaceous materials found in nature. We show that the self-organizing protein scaffolds can align otherwise unstructured components (such as fluorophores) within the macroscopic films. Multiscale self-assembly that relies on highly specific biomolecular interactions is an attractive path for realizing new multifunctional materials built from the bottom up.