Magnetic resonance hyperthermia of tumor cells

Heating of the ferrihydrite ($\mathrm{Fe}_{2}\mathrm{O}_{3}\cdot(\mathrm{H}_{2}\mathrm{O})$), hematite ($\alpha$-$\mathrm{Fe}_2\mathrm{O}_3$), maghemite ($\gamma$-$\text{Fe}_{2}\mathrm{O}_3$), cobalt ferrite ($\mathrm{CoFe}_2\mathrm{O}_4$) powders in the ferromagnetic resonance (FMR) mode has been studied. It is shown that the temperature increment is determined by the magnetization of the powders and depends linearly on the squared magnetic component of a microwave field. It is demonstrated by the example of $\mathrm{CoFe}_2\mathrm{O}_4$ that heating of magnetic powders in the FMR mode can occur by means of the natural ferromagnetic resonance. The $\gamma$-$\text{Fe}_{2}\mathrm{O}_3/\text{SiO}_2/\text{NH}_2/\text{FAS9}$ composite particles capable of effectively binding to tumor cells of Ehrlich ascites carcinoma have been synthesized. It is shown that magnetic resonance hyperthermia leads to a decrease in the viability of tumor cells.