Accurate determination of the specific absorption rate in superparamagnetic nanoparticles under non-adiabatic conditions

We report on a general description of non-adiabatic calorimetry measurements for improving the accuracy on the determination of the specific absorption rate of superparamagnetic nanoparticles subjected to alternating magnetic fields. We perform experiments on reduced volumes of iron oxide nanoparticles dispersed in aqueous media under different thermal equilibrium conditions. We introduce a simple model, which considers linear thermal losses to precisely reproduce the complete time evolution of temperature. The control and the quantification of heat losses lead to higher accuracy for determining the specific absorption rate in superparamagnetic nanoparticles. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4742918]