Thermochemiluminescence as a technique for radio frequency radiation dosimetry

Abstract

Radio frequency radiation (RFR) dosimetry is based on the rate of absorbed energy (specific absorption rate: SAR) per unit mass. It is most conveniently measured by acquiring changes in temperature per unit time and converting the results to joules per second (watts) per kilogram, based on the specific heat of the biological material interacting with the RFR. To date, SAR has been predicted by modeling based on the dielectric properties of tissues, or measured by infrared (IR) thermography or with macroscopic high-resistance thermistors or thermofluorescent macroscopic point probes. Thermochemiluminescence (TCL) was invented to provide a high degree of continuous spatial and temporal thermal resolution in phantoms. It is defined as the steady-state emission of visible light from a peroxidizing mixture based on the temperature of the mixture. The best material for this purpose, to date, is diazoluminomelanin (DALM). Unfortunately, standardization of the synthesis (chemical composition) of this polymer and its thermal response constant (thermal quantum efficiency) has been difficult. This paper presents a biosynthetic method for the large-scale production of the polymer and a computational method for directly determining the SAR from the luminescence.