Thermal traits of MNPs under high-frequency magnetic fields: Disentangling the effect of size and coating

0541422 - ÚFCH JH 2022 RIV CH eng J - Journal Article
Aurélio, D. - Mikšátko, Jiří - Veverka, M. - Michlová, Magdalena - Kalbáč, Martin - Vejpravová, J.
Thermal traits of MNPs under high-frequency magnetic fields: Disentangling the effect of size and coating.
Nanomaterials. Roč. 11, č. 3 (2021), č. článku 797. E-ISSN 2079-4991
R&D Projects: GA MŠMT(CZ) EF16_013/0001821
Grant - others:GA MŠk(CZ) CZ.02.1.01/0.0/0.0/16_013/0001821
Institutional support: RVO:61388955
Keywords : Effective magnetic anisotropy * Magnetic fluid hyperthermia * Magnetic nanoparticles * Specific power absorption * Squid magnetometry * Surface coating
OECD category: Physical chemistry
Impact factor: 5.719, year: 2021
Method of publishing: Open access

We investigated the heating abilities of magnetic nanoparticles (MNPs) in a high-frequency magnetic field (MF) as a function of surface coating and size. The cobalt ferrite MNPs were obtained by a hydrothermal method in a water–oleic acid–ethanol system, yielding MNPs with mean diameter of about 5 nm, functionalized with the oleic acid. By applying another cycle of hydrothermal synthesis, we obtained MNPs with about one nm larger diameter. In the next step, the oleic acid was exchanged for 11-maleimidoundecanoic acid or 11-(furfurylureido)undecanoic acid. For the heating experiments, all samples were dispersed in the same solvent (dichloroethane) in the same concentration and the heating performance was studied in a broad interval of MF frequencies (346–782 kHz). The obtained results enabled us to disentangle the impact of the hydrodynamic, structural, and magnetic parameters on the overall heating capabilities. We also demonstrated that the specific power absorption does not show a monotonous trend within the series in the investigated interval of temperatures, pointing to temperature-dependent competition of the Brownian and Néel contributions in heat release.
Permanent Link: http://hdl.handle.net/11104/0318981