We report a general strategy for designing and synthesizing inorganic nanostructures with arbitrarily prescribed three-dimensional shapes. Computationally designed DNA strands self-assemble into a stiff “nano-mold” that contains a user-specified three-dimensional cavity and encloses a nucleating gold “seed”. Under mild conditions, this seed grows into a larger cast structure that fills and thus replicates the cavity. We synthesized a variety of nanoparticles with three nanometer resolution: three distinct silver cuboids with three independently tunable dimensions, silver and gold nanoparticles with diverse cross sections, and composite structures with homo-/heterogeneous components. The designer equilateral silver triangular and spherical nanoparticles exhibited plasmonic properties consistent with electromagnetism-based simulations. Our framework is generalizable to more complex geometries and diverse inorganic materials, offering a range of applications in biosensing, photonics, and nanoelectronics.

We are developing synthetic peptides that non-covalently attach to natural proteins, augmenting their properties and developing novel hybrid functional materials. Using a set of hydrophobic-residue containing collagen-mimetic peptides that self-assemble into nanodiscs, we aim to encapsulate membrane proteins, increase protein hydrogel hydrophobicity, and create novel materials using structural proteins. Preliminary results suggest nanodisc interactions with the reaction center-light harvesting complex I (RC-LH1) could elucidate additional RC-LH1 structural and functional information, useful for the development of next generation solar cells. Furthermore, electron micrographs of nanodiscs embedded in collagen type I (COL I) hydrogels provide evidence for the enhancement of hydrophobic properties of COL I, and the potential for sequestering hydrophobic molecules for drug delivery. Lastly, nanodisc induced assembly of the structural protein tropomyosin is explored with the intent of enhancing the structural properties of COL I hydrogels.