title: Magnetoacoustic Sensing of Magnetic Nanoparticles.
abstract: The interaction of magnetic nanoparticles and electromagnetic fields can be determined through electrical signal induction in coils due to magnetization. However, the direct measurement of instant electromagnetic energy absorption by magnetic nanoparticles, as it relates to particle characterization or magnetic hyperthermia studies, has not been possible so far. We introduce the theory of magnetoacoustics, predicting the existence of second harmonic pressure waves from magnetic nanoparticles due to energy absorption from continuously modulated alternating magnetic fields. We then describe the first magnetoacoustic system reported, based on a fiber-interferometer pressure detector, necessary for avoiding electric interference. The magnetoacoustic system confirmed the existence of previously unobserved second harmonic magnetoacoustic responses from solids, magnetic nanoparticles, and nanoparticle-loaded cells, exposed to continuous wave magnetic fields at different frequencies. We discuss how magnetoacoustic signals can be employed as a nanoparticle or magnetic field sensor for biomedical and environmental applications.
authors.affiliation: Cardiovascular Research Center, Cardiology Division, Massachusetts General Hospital, Harvard Medical School, 185 Cambridge Street, Boston, Massachusetts 02114, USA.|Chair for Biological Imaging, Technische Universität München, Trogerstraße 9, 81675 München, Germany.|Institute for Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Kellnberger
authors.affiliation: Chair for Biological Imaging, Technische Universität München, Trogerstraße 9, 81675 München, Germany.|Institute for Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.|Andrew and Erna Viterbi Faculty of Electrical Engineering, The Technion-Israel Institute of Technology, Haifa 32000, Israel.
authors.forename: Amir
authors.initials: A
authors.lastname: Rosenthal
authors.affiliation: Institute for Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.|Institute of Developmental Genetics (IDG), Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.
authors.forename: Ahne
authors.initials: A
authors.lastname: Myklatun
authors.affiliation: Institute for Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.|Institute of Developmental Genetics (IDG), Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.|Department of Nuclear Medicine, Technische Universität München, Ismaninger Str. 22, 81675 München, Germany.
authors.forename: Gil G
authors.initials: GG
authors.lastname: Westmeyer
authors.affiliation: Department of Electrical and Computer Engineering, Aristotle University, Egnatia Str., 54124 Thessaloniki, Greece.
authors.forename: George
authors.initials: G
authors.lastname: Sergiadis
authors.affiliation: Chair for Biological Imaging, Technische Universität München, Trogerstraße 9, 81675 München, Germany.|Institute for Biological and Medical Imaging, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764 München, Germany.
authors.forename: Vasilis
authors.initials: V
authors.lastname: Ntziachristos
mesh_terms: D000162:Acoustics; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D008280:Magnetics / Q000295:instrumentation / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008962:Models, Theoretical; D013816:Thermodynamics
chemical_list: D058185:Magnetite Nanoparticles