Synthesis and characterization of luminescent and magnetic materials for biological applications

This thesis was focused on the study of luminescent and/or magnetic nanocomposites that could be destined to biological applications. Luminescent composites based on a SiO2 matrix doped with various lanthanide compounds (Eu(DBM)3Phen, ZrO2:RE3+, RE = Eu, Tb, Er/Yb) were investigated. These systems showed satisfying optical properties, morphological and structural regularity and efficient functionalization. Moreover, the possibility to obtain functionalizable nanocomposites with up-converting properties was demonstrated. Sr2MgSi2O7:Eu2+,Dy3+ persistent luminescence materials were also studied. An optimal composition of (Sr0.97Eu0.01Dy0.02)2MgSi2O7, both for the strength and the duration of the persistent luminescence, was determined. Magnetic composites made of FeOx and CoFe2O4 embedded into mesoporous SiO2 were obtained and studied, while the incorporation of Fe(0) was not achieved. By selecting the most suitable luminescent and magnetic species in terms of desired coexistence, the production of a bifunctional luminescent and magnetic system (FeOx/Eu(DBM)3Phen@ms-SiO2F) with regular morphology and nanostructure was obtained.