Cu-Ni alloy magnetic nanoparticles for hyperthermia at prescribed temperature
A.A. Kuznetsov, V.G. Leontiev, V.A. Brukvin, B.Ya. Kogan, O.A. Kuznetsov and O.A. Shlyakhtin Institute of Biochemical Physics, Russian Academy of Sciences, RU
Keywords: magnetic hyperthermia, nanopowders, smart materials, Cu-Ni alloys
Abstract: The most frequently used mediators for magnetic hyperthermia are Fe3O4 - based ferrofluids. Substantial drawback of these materials is a possibility of necrosis of the normal cells due to local overheating caused by nonuniform Fe3O4 particles distribution in the tissue. This problem could be solved by the application of ferro- and superparamagnetics with Tc = 45-60°C and considerable absorption of alternate magnetic field (AMF) at room temperature. One of the perspective classes of such materials is Cu-Ni alloys demonstrating reasonable Curie points and good biocompatibility. Nanocrystalline and loosely agglomerated Cu-Ni alloy powders were obtained by hydrogen reduction of coprecipitated hydroxides at elevated temperatures. Directed variation of Tc can be realized in Cu-Ni alloys both by the variation of Cu/Ni ratio and by the proper selection of hydrogen reduction temperature. Another important factor for the application of these mediators in hyperthermia is the rate of demagnetization in the vicinity of Tc. The maximum value of this parameter promotes faster stabilization of target temperature. It was shown that demagnetization rate also demonstrates strong correlation with thermal reduction parameters of Cu-Ni powders. Specific power absorption rate (SAR) of these mediators can be significantly enhanced by the magnetic separation of Cu-Ni nanopowders.
Back to Program
Nanotech 2006 Conference Program Abstract
|