Interactions and Exciton Transfer in DNA-Based Discrete Nanocrystal Assemblies

Discrete superstructures of nanocrystals exhibit unique optical properties which are not exhibited in separate nanocrystals. DNA has been used to self-assemble nanoparticles into assemblies with good control over the geometry and interparticle separation of the constituent nanocrystals. Electrophoresis allows purification of the nanocrystals with one DNA strand per particle, therefore, provides flexibility to form a library of nanostructures. The study quantified the optical response of QD:AuNP, QD:QD homostructures, and QD:QD FRET in heterostructures for dimers and core-satellite-assemblies. The spectral overlap, number of nanocrystals in the assembly, and interparticle separation affect the interaction between the nanocrystals and therefore, their optical properties.