A Universal high accuracy wearable pulse monitoring system via high sensitivity and large linearity graphene pressure sensor

Abstract Long-term accurate pulse monitoring can provide much physiological parameter information in a non-invasive way. A versatile pressure sensor with high sensitivity over a wide linear range (up to 10 kPa) is thus especially desired for this purpose. However, the trade-off between linearity region and sensitivity has not been well balanced. Despite micro/nanostructure morphologies, our simulation and mechanism analyses found that a thinner structure and better conductivity property of the sensing layer contribute to a larger linearity range and higher sensitivity, respectively. However, these two properties are often difficult to achieve simultaneously in one traditional material. Herein, a novel material design strategy is developed to fabricate a self-assembled graphene sensing film, in which the conductivity and thickness can be well balanced. As a result, our sensor exhibits unprecedented comprehensive properties with both high sensitivity (1875.53 kPa−1) and wide linear detection range (0–40 kPa). The sensor is also endowed with good stability and high peak signal-noise ratio (78 dB). Taking advantages of these performances, a universal high accuracy wireless and wearable pulse monitoring system was built. This platform first provides the subtle arterial pulse signal information even under the interference of strong body movement in real-time (during running or cycling), which could not have been realized before. This wearable system is expected to provide more rich and accurate information for personalized diagnostic applications in the future.