Spectrally and Spatially Tailored Gold/Silica/Ytterbium, Erbium Doped Yttria Core/Shell Nanorods For Theranostic Applications

Spectrally and Spatially Tailored Gold/Silica/Ytterbium, Erbium Doped Yttria Core/Shell Nanorods For Theranostic Applications

            Besides their reduced size, the technologically disruptive potential of nanoparticles rests with their ability to gather several complementary properties in the same object. For example, fluorescent/magnetic nanoparticles combine the high sensitivity of fluorescence imaging with the high spatial resolution of magnetic resonance imaging, while plasmonic/fluorescent nanoparticles combine the photo-thermal properties of plasmonic materials with fluorescence imaging, enabling simultaneous bio-imaging and photo-thermal therapy.

            Spectrally and spatially tailored, Au/SiO₂/Yb:Er:Y₂O₃ plasmonic/fluorescent core/shell nanorods were synthesized. The photonic modes of the fluorescent component were spectrally and spatially matched to the gold nanorod plasmonic modes by controlling the gold nanorod aspect ratio (spectral mode match) and the silica spacer layer thickness (spatial mode match). The spectrally-tailored hybrid plasmonic/fluorescent nanoparticles exhibited a more intense emission signal, a shorter spontaneous emission lifetime and a non-linear optical power dependence compared to the fluorescent material. The material also showed similar cyto-toxic and photo-thermal properties compared to polystyrene-coated gold nanorods. In photo-thermal therapy treatment tests, we were able to induce selective hyperthermia of breast cancer tissue both in-vitro and in-vivo using these hybrid nanomaterials as photosensitizers.

           

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