Magnetic iron oxide nanoparticles as drug delivery system in breast cancer

► Iron oxide nanoparticles with high magnetization and superparamagnetic properties were produced by laser pyrolysis. ► NPs internalization in the cytoplasm has a concentration dependent anti proliferative effect on MCF-7 tumor cells. ► The loading mechanism of Violamycine B1 on NP is assumed to rely on the electrostatic interactions. ► The anti-tumor activity of VB1 loaded on NP was maintained but the apoptosis process is delayed. ► NP drug delivery system should provide more drug accumulation at tumor site reducing the side effects of chemotherapy.