Magnetic Properties, Self-Temperature Rising Characteristics, and Biocompatibility of NiFe$_2$O$_4$Nanoparticles for Hyperthermia Applications

Abstract

This paper reports first on the very promising self-heating and temperature rising characteristics of solid-state NiFe <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_2$</tex> O <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_4$</tex> nanoparticles for hyperthermia applications. NiFe <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_2$</tex> O <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_4$</tex> nanoparticles were prepared by using both the “high temperature thermal decomposition method (HTTD)” and the “newly modified sol-gel” methods. The magnetic properties and cell-cytotoxic properties of the synthesized NiFe <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_2$</tex> O <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_4$</tex> nanoparticles were investigated to consider these nanoparticles for in vivo hyperthermia applications. The saturation magnetic moments measured by a high sensitive SQUID were between 43.0 and 47.6 emu/g. The cell survival rates of NiFe <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_2$</tex> O <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_4$</tex> and chitosan coated NiFe <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_2$</tex> O <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$_4$</tex> , which were determined by MTT assay, around 85 % and 98.8 %, respectively. The maximum self-heating temperature induced by our specially designed RF-MRI modified L-C circuit was 47.3 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$^circ$</tex> C and the frequency and magnetic field product, <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$H_0f$</tex> was 1.07 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$times$</tex> 10 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$^9$</tex> Am <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$^-1$</tex> s <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$^-1$</tex> .