Modelling the effect of different core sizes and magnetic interactions inside magnetic nanoparticles on hyperthermia performance

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:477

Article

Jonasson, Christian¹  Schaller, Vincent²  Zeng, Lunjie²  Olsson, Eva²  Frandsen, Cathrine³  Castro, Alejandra⁴  Nilsson, Lara⁴  Bogart, Lara K.⁵  Southern, Paul⁵  Pankhurst, Quentin A.⁵  Morales, M. Puerto⁶  Johansson, Christer¹ 

[1] RISE Acreo, Gothenburg, Sweden

[2] Chalmers Univ Technol, Dept Phys, Gothenburg, Sweden

[3] Tech Univ Denmark, Dept Phys, Lyngby, Denmark

[4] Solve AB, Lund, Sweden

[5] UCL, UCL Healthcare Biomagnet Lab, London, England

[6] CSIC, Inst Mat Sci Madrid ICMM, Madrid, Spain

关键词: Magnetic nanoparticles;    Magnetic interactions;    Magnetic relaxation;    Monte-Carlo simulations;    Multi-core particles;    Single-core particles;   

DOI  :  10.1016/j.jmmm.2018.09.117

来源: Elsevier

【 摘 要 】

We present experimental intrinsic loss power (ILP) values, measured at an excitation frequency of 1 MHz and at relatively low field amplitudes of 3.4-9.9 kA/m, as a function of the mean core diameter, for selected magnetic nanoparticles (MNPs). The mean core sizes ranged from ca. 8 nm to 31 nm. Transmission electron microscopy indicated that those with smaller core sizes (less than ca. 22 nm) were single-core MNPs, while those with larger core sizes (ca. 29 nm to 31 nm) were multi-core MNPs. The ILP data showed a peak at core sizes of ca. 20 nm. We show here that this behaviour correlates well with the predicted ILP values obtained using either a non-interacting Debye model, or via dynamic Monte-Carlo simulations, the latter including core-core magnetic interactions for the multi-core particles. This alignment of the models is a consequence of the low field amplitudes used. We also present interesting results showing that the core-core interactions affect the ILP value differently depending on the mean core size.

【 授权许可】

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