Wireless smartphone-assisted personal healthcare monitoring system using a MoS ₂ -based flexible, wearable and ultra-low-cost functional sensor

Abstract

Flexible, wearable, functional sensors that can quantify electrical signals generated by human activities are of great importance in personal healthcare monitoring. However, the high fabrication cost of these sensors along with the unreliable front-end processing of data restricts their widespread usage. In this report, we demonstrate MoS 2 growth on Al foil which was further integrated onto eraser substrate to develop smart, low-cost motion sensors (pedometer and gesture communication) and a breath sensor by measuring physiological parameters such as strain, touch and hydration levels of lungs, respectively. The data generated are wirelessly transmitted to the smartphone via Bluetooth and analyzed using dedicated Android applications for individual sensing displays. For the pedometer, the fabricated sensor was integrated onto the knee which could then calculate the steps taken, distance covered, speed and approximate number of calories burned by the individual. Gesture communication helps deaf/dumb/paralyzed individuals to communicate with the external environment using finger movements. Breath sensing allows for the early detection of lung diseases by monitoring the hydration levels of the lungs. Furthermore, the piezotronic effect of MoS 2 on breath sensing was systematically studied, and a 56.8% increase in the response was observed under a 16% strain. The sensing mechanism for each stimulus is explained via modulation in the charge transport properties for each stimulus. The sensor exhibited excellent durability where the device performance was found to be stable even after 500 continuous bending cycles. The successful demonstration of such low-cost functional wireless personal healthcare monitoring systems for Internet of Things applications is a major step forward in flexible and wearable electronics.

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Wearable Sensing Devices for Point of Care Diagnostics

“…This change is recorded to count the number of steps. 91 Pedometer integrated with sensors to provide information such as speed, duration, type of physical activity, heart rate, energy expenditure, and breath analysis, etc., are designed for standardized medical assessment purposes. 92−97 Wireless Communication.…”

“…In response to tensile strain developed while walking, the distance between nanosheets changes which causes a change in the tunneling current. This change is recorded to count the number of steps . Pedometer integrated with sensors to provide information such as speed, duration, type of physical activity, heart rate, energy expenditure, and breath analysis, etc., are designed for standardized medical assessment purposes. − …”