DNA-assembled advanced plasmonic nanostructures

Abstract

The global vibration of the free electrons on the surface of the metal nanoparticles forms surface plasmon on the surface of the particles. When multiple nanoparticles are close to each other, the electromagnetic fields between different particles will be coupled, and the electromagnetic field strength and spatial distribution after coupling will change significantly. It is necessary to construct a plasmonic resonance structure with a precise spatial conformation and tunable optical properties, provided that the spatial arrangement of the metal nanoparticles can be precisely controlled. DNA molecules are biological macromolecules that carry genetic information. Different bases in the DNA molecule (adenine A, thymine T, guanine G, cytosine C) can hybridize to each other to form stable double helixes through strict base-pairing principle. Using this property of DNA molecules, through rational design, people can obtain DNA self-assembled nanostructures with various shapes and sizes. This field was afterward named structural DNA nanotechnology. DNA nanotechnology offers a variety of new methods for constructing novel plasmonic resonance nanostructures. Using DNA-functionalized metal nanoparticles in combination with DNA templates, a variety of static or dynamic plasmonic resonance nanostructures have been successfully constructed. The plasmon resonance nanostructures constructed by DNA self-assembly have a variety of interesting nanophotonic effects, such as chiral signals in the visible range, surface-enhanced Raman spectroscopy, and surface-enhanced fluorescence spectroscopy. Dynamic DNA self-assembly plasmon resonance nanostructures not only have good optical properties but also have good structural reconfigurability. In recent years, dynamic plasmon resonance nanostructures based on DNA self-assemblies have attracted much attention. This dynamic plasmon resonance nanostructure has a wide application space in single molecule detection and chemical reaction process monitoring. The advantages of DNA self-assembled plasmonic resonance nanostructures in nanophotonics and nanoelectronics are obvious. The controllable positioning of metal nanoparticles is achieved while self-assembly of a large number of DNA molecules, making it possible to mass-produce plasmonic nanostructures. In the next step, how to accurately locate the DNA self-assembled plasmonic resonance nanostructures has become a major problem that restricts its application on nanodevices. Moreover, the mass production of DNA assembled plasmonic resonance nanostructure is still a challenge. Another strategy for scaling up the DNA assembled plasmonic resonance nanostructure is fabrication of DNA superstructure using multiple DNA nanostructures. The development of DNA self-assembly and plasmonic resonance nanostructures makes it possible to construct nanocircuits and nano-factories for chemical reactions. It is believed that in the near future, DNA self-assembled plasmonic resonance nanostructures will glow in more fields, bringing more surprises to people.