A Wireless Cardiovascular Pressure Sensor Based on an Iontronic Film with High Sensitivity

This work presents an ultra-sensitive iontronic wireless pressure sensor. The device consists of an inductor coil and a parallel-plate capacitor for pressure sensing. A microstructured iontronic film, which was embedded on the capacitor as dielectric layer, was the key element for enhancing the device performance. Assisted by the ultrahigh capacitance of electron double layers forming at the iontronic film/electrode interface, the sensitivity of the proposed device can be remarkably increased. Externally applied pressure on the device changes the capacitance, and then induces a shift in resonant frequency, which can be wirelessly retrieved by using the phase-dip technique. The measured pressure sensitivity of the proposed device was 0.014 mmHg
^-1
, which is about 50 times larger than that of the device without iontronic film.