Metallic nanoparticles fluorophore properties

To maximize fluorophore excitation and increase the fluorescence quantum yield, the spectral properties of the metal nanoparticles need to be optimized. While spherical colloidal nanoparticles of noble metals have been well known for many years, it is only recently that there has been an explosion of reports on the preparation and properties of anisotropically-shaped materials. As will be discussed in the following sections, a wide range of morphologies can be produced, including triangular nanoplates (nanoprisms), cubes, octahedra, nanowires, nanorods and bi-pyramids. The last few years have also seen major developments in our understanding of the growth processes involved, so that now it is possible to prepare many types of shaped p>articles in a controlled fashion. 

To get a foil undo-standing how the optical properties are changed for molecules close to metal nanostructures, time resolved measurements are essential. It is naturally more difficult to investigate the relevant physical processes for fluorophores placed close to an extended nanostructure rather than for the much simpler situation of fluwophores close to a special metal nanoparticle of well known geometry. Tho-efore it is advantageous to understand these simple systems first, before going on to mt -e complex structures. 

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