Heating characteristics of ferromagnetic iron oxide nanoparticles for magnetic hyperthermia

Abstract

Heating characteristics of Fe oxide nanoparticles designed for hyperthermia were examined. Samples with coercive forces from 50 to 280 Oe(codoped magnetite) were produced with a coprecipitation technique following by hydrothermal reaction. The maximum specific loss powers (SLPs) of 420 W/g was obtained at 117 kHz (640 Oe) for a dispersant sample with coercive force of 280 Oe (ATH9D). SLPs measured on dry powder samples at 17 kHz and measured at 117 kHz on dispersant samples were compared. The measured SLP amplitudes are lower for 17 kHz and higher for 117 kHz than those expected from ferromagnetic dc minor loops. For the 117 kHz case, friction of particles in a carrier fluid (similar mechanism to Brown relaxation in superparamagnetic dispersant samples) is considered to contribute to the heating mechanism.

Measurement of Intravenously Administered <formula formulatype="inline"><tex Notation="TeX">$\gamma-{\bf Fe}_{2}{\bf O}_{3}$</tex> </formula> Particle Amount in Mice Tissues Using Vibrating Sample Magnetometer

“…5. For 50 of administration, [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] of particles was calculated to accumulate in the liver. When more than 390 of particles was administered, remarkable accumulation was observed in the liver and spleen.…”

Magnetic fluid with high dispersion and heating performance using nano-sized Fe3O4 platelets

“…Hysteresis-loss heating using ferrimagnetic or ferromagnetic nanoparticles does not require a precise particle size or driving frequency, which are essential in magnetic fluids consisting of superparamagnetic iron oxide particles. High SLP has been reported in hard spinel ferrite CoFe 2 O 4 [5], spherical cobaltcontaining iron oxide particles [6,7], FeCo nanoparticles [8], and 16 nm Fe nanocubes [9]. The problem of using metal or alloy nanoparticles for hyperthermia or thermoablation is their chemical instability in fluids.…”

Harmonic phases of the nanoparticle magnetization: An intrinsic temperature probe

“…The most commonly used approach is the calorimetric method, consisting in measuring heating rates from the initial slope of temperature versus time. [14][15][16] However, there are many factors that affect the accuracy of these methods. 17 consists in the measurement of the dynamic magnetization versus applied magnetic field.…”