Abstract EN:

This thesis work treats with the preparation of cyclodextrin and lipid based self assembled nanomaterials and its characterisation from the micro level down to the atomic level. Two different strategies have been developed for the sake of nanomaterial preparation. The first one consisted of the preparation of non covalent inclusion complexes where alpha-cyclodextrins were host molecules for single chained lipids. Four different columnar structures have been identified for the latter complexes using powder X-ray diffraction techniques. It was found that these nanomaterial structures are influenced by the i) lipid hydrocarbon chain length ii) the nature of the polar head group and iii) crystallisation conditions such as temperature of complexation reaction or crystallization kinetics. It was also shown that the compactness of the molecular structure is also a function of the hydration state of the complex (amount of bound water molecules in the structure). The characterisation of single crystals of some of those inclusion compounds, using both neutron and X-ray diffraction, permitted the determination of the molecular structure and hence the description of hydrogen bounds in the structure. The second strategy employed the synthesis of covalently bound fatty acids onto the primary face of bêta-cyclodextrin. In this fashion, statistically substituted amphiphiles have been obtained. Their capacities to self assemble in the aqueous phase for the formation of nanoparticles has been determined after their composition and degree of purity had been established. Finally the formulation condition permitting stable aqueous dispersions have been developed.