Flexible and stretchable printed conducting polymer devices for electrodermal activity measurements

Highly stretchable and flexible bioelectronics should form close contact with skin and tissues while being able to withstand the stresses and strains endured by the body in order to reliably monitor physiological signals over time. Here, we report highly stretchable poly 3,4-ethylenedioxythiophene: polystyrene sulfonate (PEDOT:PSS) films printed on thermally resistant polyurethane (TPU) substrates. We established the stability of the conductivity of the devices under high strains up to 600%. The printed PEDOT:PSS film enabled the fabrication of printed organic electrochemical transistors (OECTs) with an ON/OFF ratio of 450 on a flexible substrate. We also acquired physiological signals from measuring the skin conductance arising from changes in sweat volume by directly interfacing a printed PEDOT:PSS-based sensor on TPU with human skin. Stretchable printed PEDOT:PSS films on TPU provide a facile method of producing highly stable stretchable sensors for bioelectronic applications, enabled with simple and direct printing fabrication.