Hyaluronic acid is a highly hydrated polysaccharide of great biological interest. It can be easily chemically modified, resulting in many kinds of functional polysaccharide derivatives. In this thesis, we have synthesized different types of HA derivatives in aqueous media. These comprise alkylated HA derivatives, HA-cyclodextrin conjugates, and hybrid copolymers made of HA and of a thermosensitive ethylene glycol copolymer. Based on the ability of alkylated HA and cyclodextrin grafted HA to accomodate hydrophobic molecules paclitaxel into their hydrophobic “nanocavities”, we then demonstrated the formation of polyelectrolyte multilayer capsules based on these HA derivatives. The loading of PTX in the nanoshell was achieved by first complexing PTX with HA derivatives in solution and then, depositing these PTX-containing polyelectrolytes alternately with poly(L-lysine) according to the layer-by-layer technique. In the two cases, the PTX loaded capsules were found to decrease the viability and proliferation of MDA MB 231 breast cancer cells, while unloaded capsules did not impact cell viability. Due to these promising results, these hydrophobic polysaccharide nanoshells open new avenues for applications of hydrophobic drug-carrier systems in nanomedicine.Thiol modified poly(diethyleneglycolmethacrylate - oligoethyleneglycolmethacrylate (poly(DEGMA-co-OEGMA)) was reacted with a HA-maleimide conjugate to obtain HA- poly(DEGMA-co-OEGMA). The LCST value of this HA-copolymer was determined to be around 35°C via turbidity measurements. At the body temperature, HA-copolymer was thus shown to self-assemble into nanogels with the ability to encapsulate hydrophobic molecules into their hydrophobic domain. . In vitro cell culture studies showed that with incorporating the hydrophobic anti-cancer drug paclitaxel, the nanogels exhibited high efficiency and selectivity in the eradication of CD44 positive human ovarian cancer cells. These results suggest that these temperature-triggered nanogels hold great potential for the delivery of chemotherapeutics in anti-cancer therapy.
