Ultra magnetic liposomes for MR imaging, targeting, and hyperthermia.

Magnetic liposomes offer opportunities as theranostic systems. The prerequisite for efficient imaging, tissue targeting or hyperthermia is high magnetic load of these vesicles. Here we describe the preparation of Ultra Magnetic Liposomes (UMLs), which may encapsulate iron oxide nanoparticles in a volume fraction of up to 30%. This remarkable magnetic charge provides UMLs with high magnetic mobilities, MRI relaxivities, and heating capacities for magnetic hyperthermia. Moreover, these UMLs are rapidly and efficiently internalized by cultured tumor cells and, when they are administered to mice, they can be vectorized to tumors by an external magnet.