Search

Dendronized gold nanoparticles (AuNPs) were synthesized bearing charged peripheral groups. Two novel AB3-type dendrons were synthesized with a thiol group at the focal point followed by their attachment to AuNPs. Dendrons were designed to have nine charged peripheral groups (carboxyl or amine), glycol solubilizing, units and one thiol moiety at the focal point. Both dendrons and all intermediates were synthesized in high yields and characterized by nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS). The amine- and carboxyl-terminated dendrons were used to functionalize gold nanoparticles (AuNPs) previously stabilized with citrate. The nanoparticles’ diameters and their colloidal stability were investigated using dynamic light scattering (DLS). The size and morphology of the dendronized AuNPs were evaluated by scanning electron microscopy (SEM), which revealed individual particles with no aggregation after replacement of citrate by the dendrons, in agreement with the DLS data. The absorption spectroscopy reveals a prominent plasmonic band at 560 nm for all AuNPs. The zeta potential further confirmed the expected charged structures of the dendronized AuNPs. Considering all the physical–chemical properties of the charged dendronized AuNPs developed in this work, these AuNPs might be used as a weapon against multi-drug resistant bacterial infections.

Cancer is a worldwide leading cause of death, 7.6 million deaths in 2008 with 13% mortality. Although much progress has been made in early cancer diagnosis and treatment, new approaches are needed to minimize the deleterious side effects while increasing survival rate. Therefore, the future of Nanomedicine relies in the development of multifunctional nano-platforms that combine therapeutic components, multimodal imaging and active targeting. Organic/inorganic dendrimer-based hybrids are very advanced tools, especially for targeting a specific cell type or a particular organ and for being followed by imaging techniques at the same time.In this context, the objective of this thesis is not only the design of multifunctional magnetic dendronized nano-objects, but also their in vitro and in vivo validation and assessment of their active targeting effectiveness., Le cancer est une cause majeure de décès dans le monde, 7,6 millions de décès en 2008. Bien que de nombreux progrès ont été réalisés dans le traitement du cancer, de nouvelles approches sont nécessaires afin de minimiser les effets secondaires délétères et d'augmenter le taux de survie. Par conséquent, l'avenir de la nanomédecine réside dans le développement de nano-plateformes multifonctionnelles. Il ne fait aucun doute que les hybrides organique / inorganique à base de dendrons représentent des outils très avancés, capables de cibler spécifiquement et d'être suivis par imagerie en même temps. Dans ce contexte, les objectifs de cette thèse sont non seulement la conception de nano-objets magnétiques dendronisés biocompatibles permettant à la fois le diagnostic par imagerie à résonance magnétique (IRM) ainsi que par imagerie optique (IO) mais également la validation in vitro et in vivo des propriétés de ces nano-objets et la démonstration de leur efficacité pour le ciblage spécifique de tumeurs.

Nanoparticle-cored dendrimers (NCDs) are now offering themselves as versatile carriers because of their colloidal stability, tunable membrane properties and ability to encapsulate or integrate a broad range of drugs and molecules. This kind of hybrid nanocomposite aims to combine the advantages of stimuliresponsive dendritic coatings, in order to regulate the drug release behaviour under different conditions and improve the biocompatibility and in vivo half-time circulation of the inorganic nanoparticles. Size, surface chemistry and shape are key nanocarrier properties to evaluate. Here, we have reviewed the most recent advances of NCDs in drug delivery systems, compared their behaviour with non-dendritic stabilized nanoparticles and highlighted their challenges and promising applications in the future Fil: Brunetti, Veronica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Investigaciones En Físicoquímica de Córdoba; Argentina; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Bouchet, Lydia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto de Investigaciones En Físicoquímica de Córdoba; Argentina; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Strumia, Miriam Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba; Argentina