Ion-Specific Aggregation of GoldDNA Nanoparticles Using the dG Quartet Hairpin 5′-d(G4T4G4)

Ion‐selective self‐assembly of Au nanoparticles is described. The Oxytricha telomere DNA hairpin 5′‐d(G4T4G4) immobilized on 13‐nm Au nanoparticles forms a supramolecular assembly via dG‐quartets, as determined by the color change and by scanning electron microscopy (SEM). The aggregation is ion‐dependent and selective for Na+ ions. K+ is less efficient, while Li+ and Cs+ do not drive the aggregation. This work is the first effort to explore the use of secondary structures of DNA (quadruplexes) for producing self‐assemblies of Au nanoparticles. It can be utilized to generate novel devices and materials, potentially useful for sensing and other applications in medicinal or engineering science.