Multiple design strategies of flexible piezoresistive pressure sensors in radial artery pulse signals monitoring

Noninvasive monitoring of peripheral arterial pulse wave is highly desirable for the diagnosis and prevention of cardiovascular diseases. Recently, reliable and long-term pulse wave signals monitoring through flexible pressure sensors have attracted extensive attention in both academics and industries. Here, a class of flexible piezoresistive pressure sensors with multiple types of core microstructures (nanowrinkles, microneedles, micropillars) and device-assembly designs (coplanar, sandwiched, and patch structure) have been fabricated and systematically evaluated for wearable electronic applications. With the assistance of proper external pre-loads, all types of devices can realize real-time monitoring of arterial pulse signals. The different electro-mechanical behaviors determine by the core microstructures and device assembly designs are not a simple distinction of performance, but show respective advantages to meet appropriate application requirements. This study would contribute to a common strategy for developing the next generation of wearable electronic devices in healthcare.