Wearable Multifunctional Epidermal Patch for Continuous and Reliable Blood Pressure Monitoring with Simultaneous Tracking of Physiological Health States

The development of a miniaturized version of whole‐body monitoring system has led to a large interest in the medical sector. However, the contradictory aspect of miniaturization and multifunctionality has always made the sensor's performance to degrade. In this work, a highly reliable miniaturized multifunctional epidermal patch (MEP) with multi‐physiological signal monitoring capabilities is developed for assessing and maintaining good cardiovascular conditions. The developed patch comprises of piezoresistive pulse sensor and a biogel‐enhanced electrocardiogram (ECG) sensor, along with skin hydration and thermal sensors for the first time. While simultaneous pulse signal and ECG signal allow blood pressure (BP) estimation by extraction of pulse arrival time (PAT), integrated skin temperature and hydration reflect the physiological state of the body condition and help to prevent, diagnose, and treat various diseases. Extraction of PAT parameter following a peak‐detection oriented approach, along with cardiac and pulse information when passed through a Random Forest Regression model, offers a simplistic solution for BP estimation. The results (mean ± SD) of MEP to commercial sphygmomanometer are 0.59 ± 5.03 for systolic‐BP and 0.68 ± 2.86 mmHg for diastolic‐BP, making it an optimal model. Finally, MEP is demonstrated in real‐time, showcasing its potential applicability for digital healthcare through cardiac and physiological condition monitoring.