title: Magnetic nanoparticle sensing: decoupling the magnetization from the excitation field.
abstract: Remote sensing of magnetic nanoparticles has exciting applications for magnetic nanoparticle hyperthermia and molecular detection. We introduce, simulate, and experimentally demonstrate an innovation-a sensing coil that is geometrically decoupled from the excitation field-for magnetic nanoparticle spectroscopy that increases the flexibility and capabilities of remote detection. The decoupling enhances the sensitivity absolutely; to small amounts of nanoparticles, and relatively; to small changes in the nanoparticle dynamics. We adapt a previous spectroscopic method that measures the relaxation time of nanoparticles and demonstrate a new measurement of nanoparticle temperature that could potentially be used concurrently during hyperthermia.
authors.affiliation: Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Hall, Hanover, NH 03755.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Reeves
authors.affiliation: Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Hall, Hanover, NH 03755.
authors.forename: John B
authors.initials: JB
authors.lastname: Weaver
keywords: Brownian rotation; Langevin equation simulations; Magnetic nanoparticles; biosensors