INSTITUT NEEL Grenoble Proposition de stage Master 2 - Année universitaire 2014-2015 Organic@silicates core-shell nanoparticles for diagnosis and therapy of cancers Cadre général : An original process, based on a spray drying method has been developed at the Institut Néel for the fabrication of core-shell nanoparticles composed of an organic nanocrystal as the core and a silica or organosilica layer as the shell. Using in the core dyes that are fluorescent under two-photon excitation, and taking advantage of the functionalization enabled by the silica shell, these particles might find important application as tracers for intravital imaging. Sujet exact, moyens disponibles : In tumor biology, imaging of new vessel growth or angiogenesis during tumor growth is important in the evaluation of new treatment protocols. Most medical imaging methods lack the spatial resolution to detect microscopic changes at the capillary level. Two-photon microscopy is the only technique that allows in vivo imaging of these vascular changes at a microscopic scale, but to be used it requires bright fluorescent tracers that can be water-dispersible and colloidally stable. The development of this project is based on the preparation of core-shell nanoparticles constituted by fluorescent molecular nanocrystals surrounded by amorphous silicate shells that can be easily biotargeted. This sol-gel synthesis involves the accurate control of the confined nucleation and growth of organic nanocrystals in the core of silicate spheres during spray-drying. Recently, promising results have been obtained on brain angiography on mices under two-photon excitation: particles featuring the CMONS dye in the core display a strong luminescence, but are rapidly eliminated from the blood stream to the spleen. The aim of the forthcoming studies is to develop the functionalization of such nanoparticles not only to render them furtive, but also to be able to target cancer cells by binding to the RGD receptor. In particular, co-condensation of mono- and bis-silylated organosilanes during the spray-drying process will be studied, using clickable organosilanes. This project lies at the interface between chemistry, biology and physics, and is based on the skills of MatONLP staff in organosilane, sol-gel and functionalization chemistries, as well as colloidal stabilization and luminescence. Furthermore, advanced photophysics, characterizations and in vivo / in vitro studies will be performed through already existing collaborations. Interactions et collaborations éventuelles : B van der Sanden, GIN-Clinatec, Grenoble Ce stage pourra se poursuivre par une thèse (demande de bourse en fin de stage). Formation / Compétences : M2 nanochemistry. Good knowledge on molecular chemistry, Sol-gel chemistry, colloidal suspension and spectroscopy (absorption, fluorescence, IR…) Période envisagée pour le début du stage : February 2015 Contact : Dubois Fabien and Cattoën Xavier Institut Néel - CNRS : tél : 04 76 88 74 10 mel : [email protected], [email protected] Plus d'informations sur : http://neel.cnrs.fr