Surface-enhanced Raman scattering (SERS) is a powerful analytical tool that can detect minute amounts of molecules adsorbed on rough metal surfaces. Metal nanostructures are excellent SERS surfaces because of the high magnetic fields generated in tiny gaps between nanoparticles.

Luis Liz-Marzán, CIC biomaGUNE, San Sebastian, Spain, and colleagues were able to grow SERS-ready vertical gold nanowires in an efficient, uniform and reproducible way. The nanowires were grown on aminosilane functionalized glass via seeding and self-assembly of the gold particles. The nanowire diameter and length were controlled by the ratio of mercaptobenzoic acid to Au(III) in the solution and the growth time.
The resulting substrates were able to detect micromolar amounts of chemicals like malachite green, a toxic fungicide typically used in aquaculture. The substrates are cleanable and reusable without destroying the nanowires.

• Gold Nanowire Forests for SERS Detection,
  Andrea La Porta, Marek Grzelczak, Luis M. Liz-Marzán,
  ChemistryOpen 2014, 3, 146–151.
  DOI: 10.1002/open.201402009