Wireless, intraoral hybrid electronics for real-time quantification of sodium intake toward hypertension management

Significance We introduce a soft, low-profile, intraoral electronics that offers continuous real-time monitoring of sodium intake via long-range wireless telemetry. The stretchable, hybrid electronic system integrates chip-scale components and microstructured sodium sensors with stretchable interconnects, together in an ultrasoft, breathable, microporous membrane. The quantitative computational and experimental studies of antenna performance optimize the wireless electronics, offering consistent functionality with minimal loss during multimodal deformation. Examples of in vivo study with human subjects demonstrate a highly sensitive, real-time quantification of sodium intake. Recent wearable devices offer portable monitoring of biopotentials, heart rate, or physical activity, allowing for active management of human health and wellness. Such systems can be inserted in the oral cavity for measuring food intake in regard to controlling eating behavior, directly related to diseases such as hypertension, diabetes, and obesity. However, existing devices using plastic circuit boards and rigid sensors are not ideal for oral insertion. A user-comfortable system for the oral cavity requires an ultrathin, low-profile, and soft electronic platform along with miniaturized sensors. Here, we introduce a stretchable hybrid electronic system that has an exceptionally small form factor, enabling a long-range wireless monitoring of sodium intake. Computational study of flexible mechanics and soft materials provides fundamental aspects of key design factors for a tissue-friendly configuration, incorporating a stretchable circuit and sensor. Analytical calculation and experimental study enables reliable wireless circuitry that accommodates dynamic mechanical stress. Systematic in vitro modeling characterizes the functionality of a sodium sensor in the electronics. In vivo demonstration with human subjects captures the device feasibility for real-time quantification of sodium intake, which can be used to manage hypertension.