Figure 5.

Principle of Magnetic Hyperthermia. Magnetic hyperthermia relies on the preferential accumulation of MNPs at tumors compared to normal tissues. Targeted MNPs delivered to the tumor are exposed to an alternating current (AC) magnetic field, causing nanoparticles to absorb energy by increasing alignment (lower entropy state) with the applied field. This energy is then converted to heat when the particles undergo relaxation. Tumors have been shown to possess thermal hypersensitivity, compared to normal tissues, when heated to temperatures ranging from 41–47°C. The concern for overheating normal tissues remains, however, presenting an important limitation to this method.