Ni-Cu Nanoparticles and Their Feasibility for Magnetic Hyperthermia*

Ni-Cu nanoparticles (NPs) synthesized by reducting Ni and Cu from metal precursors using a sol–gel route and annealing at 300 °C for 1, 2, 3, 6, 8, and 10 h for controlled self-regulating magnetic hyperthermia (MH) applications. Morphology and crystal structure revealed spherical NPs with cubic structure and average size of 50, 60, 53, 87, and 87 nm for as-made and annealed samples. Ferromagnetic behavior with Ms 13–20 emu/g at 300 K. ZFC-FC curves revealed superparamagnetic Nps with blocking temperature (TB) of 196–260 K. Heating rate 0.1-1.7 °C/min and specific absorption rate (SAR) of 6–80 W/g. Saturation at Curie temperature (Tc) 30–61 °C within the therapeutic temperature limit. In vitro cytotoxicity test of these Ni-Cu samples performed via exposing human breast cancer MDA-MB231 cells to a gradient of concentrations of the sample with 53 nm particles (annealed at 300 °C for 3 h) revealing biocompatibility for future in vitro/in vivo MH treatment of cancer.