Magnetoliposome for alendronate delivery

Abstract

Encapsulation into liposomes has been developed in order to allow protection of therapeutical agents against enzymatic degradation, and to reduce doses and toxic side effects. Selective, targeted and controlled release of the drug out of the lipid vesicle is still, however, difficult to achieve. Meanwhile, thanks to their magnetic properties, superparamagnetic iron oxide (SPIO) nanoparticles have also been considered as good delivery vehicles after grafting a therapeutic drug on their surface. A combination of both properties (magnetic targeting and drug encapsulation) is evaluated to deliver an anticancer drug : alendronate, an hydroxymethylene bisphosphonate molecule. γ-Fe₂O₃ nanocrystals grafted with alendronate were tested with or without liposome encapsulation, with and without magnetic field, on three human cancer cell lines, MDA-MB231, A431 and U87-MG. Cytotoxicity was measured as well as drug internalization. While results were not identical on the three cell lines with the different formulations, an effective 100% cytotoxic effect could only be achieved with alendronate grafted-SPIO entrapped into liposomes and exposed to a magnetic field.