Magnetic iron oxide nanoparticles are attracting increasing attention due to their interesting properties that can be applied in a great number of applications such as catalysis and biomedicine. This thesis focuses on the synthesis, characteristics, and biomedical applications of iron oxide nanoparticles. The two most common iron oxides, including magnetite and maghemite, are discussed in this thesis.

For most of their applications, the magnetic behavior of iron oxide nanoparticles in a fluid is very important, especially, the high gradient magnetic separation of the particles from a nonmagnetic liquid medium, such as blood in the human body. A 2D model, which represents a slice through the center of a spherical particle in a fluid, is created in this thesis, and only the magnetic force and the drag force are taken into consideration. The magnetization of the particle is calculated by using the Langevin function, and the fluid drag force is calculated by using the Navier-Stokes equation . The trajectory function for this model is calculated, and the trajectories are drawn for specific cases.