Magnetic Relaxation in Ferrimagnetic Glass-Ceramics Obtained by Co-Precipitation at Different Temperatures

Author

Tiberto, Paola ; Coisson, Marco ; Vinai, Franco ; Allia, Paolo ; Bretcanu, Oana ; Vernè, Enrica

Author_Institution

Mater. Dept., INRIM, Torino

Volume

43

Issue

6

fYear

2007

fDate

6/1/2007 12:00:00 AM

Firstpage

2471

Lastpage

2473

Abstract

Magnetic induction hyperthermia is a promising technique aimed at the treatment of cancer cells; however, the efficiency of the heat release is determined by the magnetic stability of the system. Ferrimagnetic glasses composed of magnetite and hematite crystals in a glassy matrix were prepared by melting of commercial reagents. The time evolution of the magnetic remanence was studied by submitting each sample to a saturating field of 20 kOe for 300 s. After sudden removal of the magnetic field, the evolution of the magnetic remanence was recorded for times up to 5times10⁴ s. In all cases, the remanent magnetization exhibits a nonsaturating, monotonic decrease of its magnitude. The results are interpreted in terms of rearrangements of disordered magnetic volumes at interfaces between adjacent magnetite crystals.

Keywords

biomagnetism; biomedical materials; cancer; cellular biophysics; ferrimagnetic materials; glass ceramics; hyperthermia; iron compounds; magnetic relaxation; precipitation; remanence; 300 s; Co-precipitation; Fe₂O₃-SiO₂-Na₂O-CaO-P₂O₅; cancer cell treatment; ferrimagnetic glass-ceramics; glassy matrix; hematite; magnetic induction hyperthermia; magnetic relaxation; magnetic remanence; magnetic stability; magnetite; melting; remanent magnetization; Cancer; Crystals; Ferrimagnetic materials; Glass; Heat treatment; Hyperthermia; Remanence; Saturation magnetization; Stability; Temperature; Biomedical materials; hyperthermia; relaxation processes;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/TMAG.2007.893845

Filename

4202946