Smart magnetic nanopowder based on the manganite perovskite for local hyperthermia.

For many medical applications related to diagnosis and treatment of cancer disease, hyperthermia plays an increasingly important role as a local heating method, where precise control of temperature and parameters of the working material is strongly required. Obtaining a smart material with "self-controlled" heating in a desirable temperature range is a relevant task. For this purpose, the nanopowder of manganite perovskite with super-stoichiometric manganese has been synthesized, which consists of soft spherical-like ferromagnetic nanoparticles with an average size of 65 nm and with a narrow temperature range of the magnetic phase transition at 42 °C. Based on the analysis of experimental magnetic data, a specific loss power has been calculated for both quasi-stable and relaxation hysteresis regions. It has been shown that the local heating of the cell structures to 42 °C may occur for a short time (∼1.5 min.) Upon reaching 42 °C, the heating is stopped due to transition of the nanopowder to the paramagnetic state. The obtained results demonstrate the possibility of using synthesized nanopowder as a smart magnetic nanomaterial for local hyperthermia with automatic heating stabilization in the safe range of hyperthermia without the risk of mechanical damage to cell structures.