The controlled and reproducible synthesis of closely spaced noble metal nanoparticle groupings is an essential step toward the rational design of nanostructures for surface enhanced Raman scattering with single-molecule sensitivity. In this communication, we demonstrate the facile synthesis of 5, 8, and 18 nm gold particle groupings on a well-defined DNA template by hybridizing monoconjugated gold-DNA building blocks. The obtained nanometer interparticle gaps should yield local intensity enhancements up to 4 orders of magnitude as estimated by Generalized Mie Theory. By tuning the particle size and relative curvatures, we calculate that the maximum enhancement can be optimized and localized on a specific part of the nanostructure. These groupings act as plasmon-based nanolenses assembled on a biomolecular backbone that can be functionalized in proximity to the region of highest field.
J. Am. Chem. Soc.
Photonic Materials

Bidault, S, García de Abajo, F.J, & Polman, A. (2008). Plasmon-based nanolenses assembled on a well-defined DNA template. J. Am. Chem. Soc., 130, 2750–2751. doi:10.1021/ja711074n