A double cell differential thermometric system for specific loss power measurements in magnetic hyperthermia

Abstract Calorimetric methods are widely used for the determination of the specific loss power (SLP) of ferrofluids utilized for magnetic hyperthermia treatments. The direct differential measurement of temperature increase under an alternating magnetic field requires a thermometric system immune to magnetic interference and to the self-heating of the sensor elements. We propose a differential thermometric system where simple thermocouples and resistance temperature detectors (RTDs) prone to self-heating can be used. The disturbing effect of the magnetic field was compensated by detecting only a differential signal between the symmetric sides of the thermometer in a double sample holder arrangement. The performance of the system was evaluated based on acquiring the heating curves and determining the SLP of various ferrofluids. At low field strength conditions ( H 0 = 0.32  kA m − 1 , f = 480 kHz) SLP of up to ( 0 . 089 ± 0 . 003 )  W g − 1 was determined.