Towards real-time and remote magnetonanothermometry with temperature accuracy better than 0.05 K

• A more accurate and realistic model for magnetonanothermometry is proposed.
• Both the particle diameter distribution and the temperature dependence of the saturation magnetization are taken account into the model picture.
• Low frequency as well as low amplitude applied magnetic fields aim to simplify the development of instrumentation.
• The novel approach provides excellent accuracy better than 0.05 K in 1 s measurement.

In this study, we report on a novel approach for real-time temperature probing using magnetization of magnetic nanoparticles as thermometric property. Differently from the existing approaches, we included diameter distribution function, f(D), and temperature dependence of saturation magnetization, MS(T), in the model picture herein used to assess temperature. Using simulation as well as experimental data, we found the new approach provides accuracy better than 0.05 K in 1 s measurement. Magnetization data were acquired using low-frequency (25 Hz) and weak triangular-wave applied AC magnetic field (amplitude below 50 Oe), allowing for the use of the first two terms of the Taylor’s expansion of the Langevin function. Experimental conditions reported in the present study are promising for developing new instrumentation to support the upcoming magnetonanothermometry technology and its application in the medical field.