DNA-Nanotechnology-Enabled Chiral Plasmonics: From Static to Dynamic.

Area of Science:

• Nanotechnology
• Plasmonics
• Biophysics

Background:

• DNA nanotechnology, particularly DNA origami, offers precise control over nanostructure assembly.
• Metal nanoparticles, such as gold nanoparticles (AuNPs), can be organized by DNA origami to create functional plasmonic systems.
• Coupling of plasmons in closely spaced metal nanoparticles leads to unique optical phenomena.

Purpose of the Study:

• To review static and dynamic chiral plasmonic nanostructures assembled using DNA nanotechnology.
• To highlight the use of circular dichroism (CD) spectroscopy for characterizing these nanostructures.
• To explore applications of these systems in areas like sensing and optical devices.

Main Methods:

• Assembly of chiral plasmonic nanostructures using DNA origami and gold nanoparticles (spherical and nanorods).
• Characterization of optical responses using circular dichroism (CD) spectroscopy.
• Engineering dynamic systems through DNA-regulated conformational changes and pH tuning.

Main Results:

• Demonstrated static chiral plasmonic structures including helices, toroids, crosses, and helical superstructures.
• Developed dynamic systems with DNA-regulated conformational switching (chiral to achiral states) and light/pH stimuli responsiveness.
• Created plasmonic walkers on DNA origami exhibiting dynamic CD responses.

Conclusions:

• DNA nanotechnology provides a versatile platform for designing sophisticated static and dynamic chiral plasmonic nanostructures.
• CD spectroscopy is crucial for detecting subtle conformational changes in these nanoscale systems.
• The integration of DNA nanotechnology and plasmonics promises novel functional optical materials and devices.