Nucleobase-driven wearable Ionogel electronics for long-term human motion detection and electrophysiological signal monitoring

Abstract

Ionogels are considered as ideal candidates for constructing flexible electronics due to their superior electrical conductivity, flexibility, high thermal and electrochemical stability. However, it remains a great challenge to simultaneously achieve high sensitivity, repeated adhesion, good self-healing, and biocompatibility through a straightforward strategy. Herein, inspired by nucleobase-tackified strategy, a multifunctional adhesive ionogel is developed through one-step radical polymerization of acrylated adenine/uracil (Aa/Ua) and acrylic acid (AA) monomers in sodium caseinate (SC) stabilized liquid metal dispersions. As a soft conductive filler, the incorporating of liquid metal not only improves the electrical conductivity, but also enhances the mechanical strength, satisfying the stretchable sensing application. The large amount of noncovalent interactions (hydrogen bonding, metal coordination, and ion-dipole interactions) within the networks enable the ionogels to possess excellent stretchability, skin-like softness, good self-healing, and strong adhesion. Based on these desirable characteristics, the ionogel is suitable for wearable strain sensors to precisely detect diverse human movements under extreme environments. Moreover, the seamless adhesion with human skin allows the ionogel to function as bioelectrode patch for long-term and high-quality electrophysiological signal acquisition. This research provides a promising strategy for designing ionogels with tailored functionalities for wearable electronics that satisfy diverse application requirements.