title: Size-Dependent Relaxation Properties of Monodisperse Magnetite Nanoparticles Measured Over Seven Decades of Frequency by AC Susceptometry.
abstract: Magnetic relaxation is exploited in innovative biomedical applications of magnetic particles such as magnetic particle imaging (MPI), magnetic fluid hyperthermia, and bio-sensing. Relaxation behavior should be optimized to achieve high performance imaging, efficient heating, and good SNR in bio-sensing. Using two AC susceptometers with overlapping frequency ranges, we have measured the relaxation behavior of a series of monodisperse magnetic particles and demonstrated that this approach is an effective way to probe particle relaxation characteristics from a few Hz to 10 MHz, the frequencies relevant for MPI, hyperthermia, and sensing.
authors.affiliation: Department of Materials Science, University of Washington, Seattle, WA 98195 USA.
authors.forename: R Matthew
authors.initials: RM
authors.lastname: Ferguson
authors.affiliation: Department of Materials Science, University of Washington, Seattle, WA 98195 USA.
authors.forename: Amit P
authors.initials: AP
authors.lastname: Khandhar
authors.affiliation: Acreo AB, SE 400 16 Göteborg, Sweden.
authors.forename: Christian
authors.initials: C
authors.lastname: Jonasson
authors.affiliation: Acreo AB, SE 400 16 Göteborg, Sweden.
authors.forename: Jakob
authors.initials: J
authors.lastname: Blomgren
authors.affiliation: Acreo AB, SE 400 16 Göteborg, Sweden.
authors.forename: Christer
authors.initials: C
authors.lastname: Johansson
authors.affiliation: Department of Materials Science, University of Washington, Seattle, WA 98195 USA.
authors.forename: Kannan M
authors.initials: KM
authors.lastname: Krishnan
keywords: AC susceptometry; magnetic particle imaging; magnetic particles; magnetization reversal