Interpenetrating PAA-PEDOT conductive hydrogels for flexible skin sensors

Conductive hydrogels are promising material candidates in artificial skin and muscles, flexible and implantable bioelectronics, and tissue engineering. However, it is still a challenging task to formulate hydrogels with high electrical conductivity without compromising their physicochemical properties. Herein, we report an interpenetrating poly(acrylic acid)-poly(3,4-ethylenedioxythiophene) (PAA-PEDOT) hydrogel with high electrical conductivity and good stretchability. A second PEDOT hydrogel network is electrochemically polymerized into an existing PAA hydrogel network. The interpenetrating hydrogel can be readily prepared and integrated into epidermal flexible electronic devices for the real-time, on-body detection of various ions in human sweat. The interpenetrating PAA-PEDOT conductive hydrogel has the potential to be an important building material for various flexible electronic devices for personalized healthcare. Conductive hydrogels are promising material candidates in artificial skin and muscles, flexible and implantable bioelectronics, and tissue engineering.