Establishing a genetic code for unnatural materials

Presented by Chad Mirkin

Abstract

Nature encodes nucleic acids to assemble enormously complex and highly functional materials that form the foundation of life. To establish a similar code to construct synthetic, unnatural materials would allow researchers to perfectly position the atoms in a material to perform a specific function. While such control is exceedingly difficult for atomic and molecular building blocks, it is possible to control the interactions between nanoscale components through the ligands attached to their surface, independent of nanoparticle structure and composition. Our group has shown that nucleic acids can be used as ligands to program the spacing and symmetry of nanoparticle building blocks into structurally sophisticated materials. These nucleic acids function as programmable "bonds" between nanoparticle "atoms" and can be analogized to a nanoscale genetic code to direct assembly. The tunability of these nucleic acids bonds, in terms of length and sequence, has allowed us to define a powerful set of design rules to build superlattices with more than 30 unique lattice symmetries, over one order of magnitude in interparticle spacing, and multiple well-defined crystal habits. These materials can dynamically respond to biomolecular stimuli, including other nucleic acids and enzymes, to tailor structure and properties on demand, analogous to how these molecules function in nature. This unique genetic approach to materials design yields nanoparticle architectures that can be used to catalyze chemical reactions, manipulate light-matter interactions, investigate energy transfer between nanostructures, and improve our fundamental understanding of crystallization processes.