Transient Response of Ion-Selective Potentiometric Wearable/Implantable Sensors

Laboratory-based potentiometric electrochemical sensors, supported by well-developed steady-state theory, have traditionally relied on endpoint detection to determine analyte concentration in various applications in agriculture, food safety, and pharmaceutical quality control, among others. In contrast, the emerging applications of wearable and implantable sensors suggest a new paradigm for real-time, continuous monitoring of analytes, for example, in healthcare and environmental monitoring. This paper develops a new analytical model for the transient response of the sensors and explains how sensor geometry, placement, and chemical properties determine the response delay. The model offers a transparent approach to optimizing sensor response, and therefore, the work would be of broad interest to sensors and system designers of not only wearable/implantable sensors, but also of modern genome-sequencers.