In a glass house: Silica-encapsulated self-assembled monolayers (SAMs) on tunable gold/silver nanoshells were used as labels for surface-enhanced Raman scattering (SERS). This concept combines the spectroscopic advantages arising from maximum surface coverage and uniform molecular orientation of the Raman reporter molecules within the complete monolayer together with the high chemical and mechanical stability of the glass shell.

The synthesis of 3D self-assembled plasmonic superstructures of gold nanospheres as well as the characterization of their structural and optical properties at the single-particle level is presented. This experimental work is complemented by FEM (finite element method) simulations of elastic scattering spectra and the spatial |E|(4) distribution for establishing structure-activity correlations in these complex 3D nanoclusters.

Surface-enhanced Raman scattering (SERS) offers a tremendous multiplexing capacity for the selective detection of biomolecules in targeted research. SERS labels comprising self-assembled monolayers (SAMs) of Raman reporter molecules on the surface of metal nanoparticles are sensitive and robust probes. Advantages of a SAM include maximum sensitivity, minimal unwanted co-adsorption of molecules from the surroundings, and reproducible SERS spectra with only few dominant Raman bands--all of these independent of a particular SERS substrate. We demonstrate experimentally how to increase the multiplexing capacity of SERS labels by using mixed SAMs with up to three different Raman reporter molecules on the surface of the metal colloid. Type and stoichiometry of a particular Raman label in a multi-component SAM are additional parameters compared with one-component SAMs. All one-, two-, and three-component SAMs on gold nanospheres can be easily discriminated, either by their original SERS spectra or the corresponding bar codes.

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SAM im Glashaus: Glasverkapselte selbstorganisierte Monolagen (SAMs) auf durchstimmbaren Gold/Silber‐Nanoschalen wurden als Markierungsreagens für die oberflächenverstärkte Raman‐Streuung (SERS) eingesetzt. Dieses Konzept vereint die spektroskopischen Vorteile einer maximalen Oberflächenbedeckung und der einheitlichen molekularen Orientierung der Raman‐Markermoleküle innerhalb der vollständigen Monolage mit der hohen Stabilität einer Glashülle.