Title：Colloid Crystal Engineering with DNA

Invited Speaker：Prof. Chad A. Mirkin

     Department of Chemistry and International Institute for Nanotechnology，           Northwestern University

Venue：Room A717, Chemistry Building

Time：3:30pm,Nov.8,2017.

Abstract：

The materials-by-design approach to the development of functional materials requires new synthetic strategies that allow material composition and structure to be independently controlled and tuned on demand. Although it is exceedingly difficult to control the complex interactions between atomic and molecular species in such a manner, interactions between nanoscale components can be encoded, independent of nanoparticle structure and composition, through the ligands attached to their surface. The Mirkin Group has shown that nucleic acids can be used as highly programmable surface ligands (“bonds”) to control the spacing and symmetry of nanoparticle building blocks (“atoms”) in structurally sophisticated materials, analogous to a nanoscale genetic code for material assembly. The sequence and length tunability of nucleic acid bonds has allowed us to define a powerful set of design rules for the construction of nanoparticle superlattices with more than 30 unique lattice symmetries, spanning over one order of magnitude of interparticle distances, with several well-defined crystal habits. Further, this control has enabled exploration of sophisticated symmetry breaking processes, including the body-centered tetragonal lattice and the most structurally complex nanoparticle-based material to date (>20 particles per unit cell). The nucleic acid bond can also be programmed to respond to external biomolecular and chemical stimuli, allowing structure and properties to be tailored on demand. Notably, this unique genetic approach to materials design affords functional nanoparticle architectures that can be used to catalyze chemical reactions, manipulate light-matter interactions, and improve our fundamental understanding of crystallization processes.