Distribution of Magnetic Nanoparticles Anisotropy Energy Estimated from AC Susceptibility and Magnetic Relaxation

摘要

Magnetic nanoparticles (MNPs) have been extensively studied for applications in biomedicine such as magnetic immunoassay, magnetic particle imaging and hyperthermia. For these applications, one of the key parameters of the MNPs is its anisotropy energy E. This is due to the strong dependence of the Neel relaxation time of MNPs on the value of E. Hence, the anisotropy energy E of MNPs should be appropriately selected in order to be suitable for the intended application. Therefore, estimation of the E distribution in MNP samples is significantly important to develop MNPs that are suited for specific applications. Distribution of E can be estimated by analyzing experimental measurement results of the magnetic properties for MNP samples, i.e., the AC susceptibility (ACS) and the magnetic relaxation (MRX) of immobilized MNP sample [1],