Effect of Heat Conditions of Pyrolysis Method on Magnetite Nanoparticles for Hyperthermia Localization

抄録

Magnetite nanoparticles are often used as heating carriers for hyperthermia applications and have recently gained attention as a cancer treatment method. The physical properties and functions of magnetic nanoparticles depend on their size and shape. Therefore, it is important to maintain a narrow size distribution and a constant shape. This study aimed to investigate the effect of varying the heating conditions in the pyrolysis method on the shape of magnetite nanoparticles. The results indicated that the size of magnetite nanoparticles increased in proportion to the increase in heating temperature due to Ostwald ripening. The particles were generally circular in shape, but some were polygonal, indicating the crystalline structure of the iron atoms. The results show the occurrence of crystal growth and Ostwald ripening. Magnetite nanoparticles should be formed under lowtemperature heating conditions to obtain a particle size of approximately 12 nm, a requirement for inducing hyperthermia. On the other hand, the particle shape was generally spherical with an aspect ratio accepted in the 1.5, which was found in a cube, indicating that shape evaluation was not highly important.