(519h) Effect of Core Material and Graft Molecular Weight On the Energy Dissipation Rate of Magnetic Nanoparticles in Oscillating Magnetic Fields

Magnetic nanoparticles subjected to high frequency oscillating magnetic fields dissipate energy in the form of heat, inducing an increase in the temperature of the surrounding medium. This effect forms the basis of emerging applications of magnetic nanoparticles in cancer treatment and in magnetically actuated drug delivery. With the objective of improving the fundamental understanding of this phenomenon, the energy dissipation from magnetite and cobalt ferrite nanoparticles with narrow particle size distribution and surface modified with grafted poly (ethylene glycol) (PEG) of different molecular weights was studied. Specific absorption rates (SARS) in water were measured for all particles and correlated to physical and magnetic nanoparticle properties, such as core size, hydrodynamic diameter, saturation magnetization, and blocking temperature.