Preparation of DNA Nanotubes Decorated With Gold Nanoparticles Based on DNA Origami

The controlled arrangement of metal nanoparticles is crucial for the development of plasmonic devices. Deoxyribonucleic acid (DNA) origami provides a template for nanoparticle assembly. Herein, the caDNAno software was used to design double-layered DNA nanotubes with capture sites for gold nanoparticles (AuNPs). Functionalized AuNPs were conjugated to the nanotubes via sequence-specific probe hybridization. The resulting hybrid nanostructures were characterized using agarose gel electrophoresis, atomic force microscopy, and transmission electron microscopy. AuNPs were found to be periodically arranged along the DNA nanotubes in a helical configuration. Ultraviolet–visible spectroscopy revealed a red shift of the localized surface plasmon resonance peak, which indicated plasmonic coupling between the helically arranged nanoparticles. Our method holds promise for optical sensing and detection.