Organic Temperature Sensitive Polyelectrolyte for Core Body Temperature Measurement

Core body temperature (CBT) is a vital phenotype that provides information on an individual’s health and metabolic activity. It correlates with a variety of physical and mental conditions and requires monitoring when an individual is under environmental or medical duress. Current sensing materials lack the desired temperature sensitivity for fabricating ultrathin, wearable CBT sensors with the accuracy needed for medical applications. Here, the realization of an ultrathin CBT sensor based on dual heat flux (DHF) thermometry is reported, uniquely enabled by the application of a novel class of synthetic polymers. By optimizing the chemical composition, the material’s properties were tuned to achieve an optimal temperature response. Furthermore, the measurement error in the device was evaluated using Finite Element analysis. Building on this knowledge, this highly temperature-sensitive polymer was embedded into an ultrathin DHF sensor, and its sensitivity and repeatability were characterized using an anthropomorphic phantom model. The results presented in this work pave the way for first-in-class wearable and accurate DHF sensors, allowing continuous CBT monitoring.