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J. Phys. Chem. C 2009, 113, 15974–15981
Photophysical Properties of Dye-Doped Silica Nanoparticles Bearing Different Types of Dye-Silica Interactions Dongling Ma,*,† Arnold J. Kell,‡ Sophie Tan,§ Zygmunt J. Jakubek,‡ and Benoit Simard*,‡ Institut National de la Recherche Scientifique, 1650 BouleVard Lionel-Boulet, Varennes, Quebec J3X 1S2, Canada, and Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada ReceiVed: June 20, 2009; ReVised Manuscript ReceiVed: August 4, 2009
Photophysical properties of three types of dye-doped silica nanoparticles (NPs) with different dye-silica interactions have been investigated. In two cases the dye-silica interactions are noncovalent, where tris(2,2′bipyridine)ruthenium(II) chloride (Rubpy) is attracted to the silica network electrostatically and tetramethylrhodamine-dextran (TMR-Dex) is trapped inside the silica matrix through spatial/steric hindrance. In the third case, tetramethylrhodamine-5-isothiocyanate (TRITC) modified with 3-aminopropyltriethoxysilane (APTES) to form TMR-APTES is bound to the silica matrix covalently. Although in all three types of architectures absorption, excitation, and emission spectra show only small red-shifts (
