title: Effects of inter- and intra-aggregate magnetic dipolar interactions on the magnetic heating efficiency of iron oxide nanoparticles.
abstract: Iron oxide nanoparticles have found an increasing number of biomedical applications as sensing or trapping platforms and therapeutic and/or diagnostic agents. Most of these applications are based on their magnetic properties, which may vary depending on the nanoparticle aggregation state and/or concentration. In this work, we assess the effect of the inter- and intra-aggregate magnetic dipolar interactions on the heat dissipation power and AC hysteresis loops upon increasing the nanoparticle concentration and the hydrodynamic aggregate size. We observe different effects produced by inter- (long distance) and intra-aggregate (short distance) interactions, resulting in magnetizing and demagnetizing effects, respectively. Consequently, the heat dissipation power under alternating magnetic fields strongly reflects such different interacting phenomena. The intra-aggregate interaction results were successfully modeled by numerical simulations. A better understanding of magnetic dipolar interactions is mandatory for achieving a reliable magnetic hyperthermia response when nanoparticles are located into biological matrices.
authors.affiliation: Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, C\Sor Juana Inés de la Cruz, 6, 28049 Madrid, Spain.
authors.forename: J G
authors.initials: JG
authors.lastname: Ovejero
authors.affiliation: iMdea Nanociencia, Campus Universitario de Cantoblanco, 28049 Madrid, Spain.
authors.forename: D
authors.initials: D
authors.lastname: Cabrera
authors.affiliation: Laboratoire de Physique et Chimie des Nano-Objets (LPCNO), Université de Toulouse, INSA, UPS, F-31077 Toulouse, France and CNRS, UMR 5215, F-31077 Toulouse, France.
authors.forename: J
authors.initials: J
authors.lastname: Carrey
authors.affiliation: iMdea Nanociencia, Campus Universitario de Cantoblanco, 28049 Madrid, Spain.
authors.forename: T
authors.initials: T
authors.lastname: Valdivielso
authors.affiliation: Instituto de Ciencia de Materiales de Madrid, ICMM-CSIC, C\Sor Juana Inés de la Cruz, 6, 28049 Madrid, Spain and iMdea Nanociencia, Campus Universitario de Cantoblanco, 28049 Madrid, Spain and Nanobiotecnología (iMdea Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC), 28049 Madrid, Spain. francisco.teran@imdea.org.
authors.forename: G
authors.initials: G
authors.lastname: Salas
authors.affiliation: iMdea Nanociencia, Campus Universitario de Cantoblanco, 28049 Madrid, Spain and Nanobiotecnología (iMdea Nanociencia), Unidad Asociada al Centro Nacional de Biotecnología (CSIC), 28049 Madrid, Spain. francisco.teran@imdea.org.
authors.forename: F J
authors.initials: FJ
authors.lastname: Teran
mesh_terms: D002151:Calorimetry; D003102:Colloids / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D013696:Temperature
chemical_list: D003102:Colloids; D005290:Ferric Compounds; C000499:ferric oxide