Functional Crystals Through Encodable Hard and Soft Matter

The ability to deliberately synthesize materials by design is one of the greatest scientific challenges of the 21st century that if met, will open access to structures that satisfy major technological needs of both the DoD and civilian communities. Novel materials are routes to breakthrough advances in electronics, photonics, and energy generation, conversion, and storage, as well as catalysis and chemical and biological sensing. The conventional way of realizing new materials is to synthesize molecules that can be used to build polymers or extended three-dimensional structures through covalent or coordination bonds dictated by atomic or molecular building blocks. In the field of nanoscience, nanoparticles often are viewed as “atoms” and macromolecules as “bonds”, and they have been used to prepare a class of materials that have extraordinary properties that derive from the arrangement of nanoconstructs in three-dimensional space. Since nanoparticles have properties that are very different from their atomic or molecular precursors and bulk material counterparts, novel materials can be synthesized and used to address technological challenges not possible with conventional materials. Under the NSSEFF we propose to develop materials-general methods for the bottom-up synthesis of macroscopic crystals comprised of nanoscale components. The nanoscale components utilized will be a diverse set of building blocks including proteins, viruses, and inorganic nanoparticles, where oligonucleotides behave as synthetically programmable bonds between nanoparticles. The programmable nature of DNA will allow for precise control over interparticle distance, crystal symmetry, and crystalline habit independent of nanoparticle composition. Additionally, since the focus of this NSSEFF proposal is on developing new functional materials, we will concurrently develop methods for stabilizing these materials in gel, polymer, and solid-state matrices for use in diverse chemical and physical environments. This proposal is separated into five primary experimental objectives, each one focused on developing an important aspect of this emerging platform (Scheme 1). They are: 1) the development and characterization of nucleic acid functionalized building blocks from both hard and soft matter particle precursors; 2) methods for guiding their assembly into superlattices with controlled crystalline morphologies; 3) novel catalytic materials with periodic architectural parameters programmable through choice of nucleic acid modified constructs, 4) the utilization of such programmable materials for developing ultrasensitive biodetection systems with unusual and potentially useful molecular recognition and amplification properties, and 5) the development of optically responsive metamaterials and devices through the ability to control single crystal formation from DNA-functionalized plasmonic nanoparticle building blocks. Novel structures and phenomena such as catalytic protein cascades, hybrid organic-inorganic superenzymes, and microscale plasmonic lasers and lenses will be realized through these studies, and a fundamentally new way of thinking about materials synthesis and crystal engineering will be developed.