Thu, 21 Aug 2008 06:48:21 BST CiteULike: rodney's Blanchard-Desce http://www.citeulike.org/user/rodney/author/Blanchard-Desce CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/rodney/article/2793329 <i>Chem. Mater., Vol. 20, No. 6. (25 March 2008), pp. 2174-2183.</i><br /><br />Abstract: The template-directed synthesis of mesoporous silica nanoparticles doped with water-soluble fluorescent dyes optimized for two-photon excitation is described. Two structurally related symmetrical two-photon dyes that possess pyridinium acceptor endgroups conjugated to a fluorenyl core are synthesized by Heck coupling. These dyes display bright fluorescence (¦ H 0.35) under both one- (µ H 6 × 104 M1 cm1) and two-photon excitation (Ã2 H 1000 GM) and were successfully encapsulated in silica nanoparticles via immobilization through noncovalent interactions. The nanoparticles present a mean diameter of 100 nm and a hexagonal network of mesopores as shown by TEM. Interestingly, the photophysical characteristics of the dyes are retained upon their immobilization into the silica matrix, leading to fluorescent silica nanoparticles with giant/unprecedented TPA cross-section (1 × 107 GM). Such nanospheres represent attractive nanoplatforms for the development of biotargeted biocompatible luminescent tracers. Synthesis and Characterization of Fluorescently Doped Mesoporous Nanoparticles for Two-Photon Excitation Val&#xe9;rie Lebret Laurence Raehm Jean-Olivier Durand Monique Sma&#xef;hi Corine G&#xe9;rardin Nicolas Nerambourg Martinus Werts Mireille Blanchard-Desce doi:10.1021/cm703487b Chem. Mater., Vol. 20, No. 6. (25 March 2008), pp. 2174-2183. 2008-05-13T03:58:28-00:00 2008 Chem. Mater. 20 6 2174 2183 characterization citedby excitation fluorescence mesoporous nanoparticles synthesis two-photon