SPION@liposomes hybrid nanoarchitectures with high density SPION association

A simple, versatile and reproducible method for the preparation of hybrid inorganic–organic magnetic nanocolloids based on phospholipids and preformed magnetic nanoparticles has been proposed. Superparamagnetic hydrophilic and hydrophobic iron oxide nanoparticles (SPION) of similar size are synthesized as a first step and subsequently hybrid-lipid based assemblies containing SPION has been prepared according to the thin film hydration method (TLE) using soya phosphatidylcholine. The effects of the different nature of the nanoparticles on the features of the assemblies have been observed by TEM: the hydrophilic nanoparticles are found to be located at the external surface of the vesicle, while the hydrophobic ones are in the inner core of the vesicles. In particular, uni/oligolamellar magnetic vesicles have been achieved with hydrophilic nanoparticles and high density multilamellar magnetic vesicles have been obtained with hydrophobic magnetic nanoparticles. “Cationic” nanoparticles interaction with “anionic” phospholipids has been proposed in the case of hydrophilic nanoparticles, while an aggregation phenomenon probably due to the hydration phase during the magnetoliposome preparation and an interaction of the oleic acid coatings with lipid membrane has been suggested in the case of hydrophobic nanoparticles.