Self-adhesive epidermal carbon nanotube electronics for tether-free long-term continuous recording of biosignals

Abstract
The long-term, continuous, inconspicuous, and noiseless monitoring of bioelectrical signals is critical to the early diagnosis of disease and monitoring health and wellbeing. However, it is a major challenge to record the bioelectrical signals of patients going about their daily lives because of the difficulties of integrating skin-like conducting materials, the measuring system, and medical technologies in a single platform. In this study, we developed a thin epidermis-like electronics that is capable of repeated self-adhesion onto skin, integration with commercial electronic components through soldering, and conformal contact without serious motion artifacts. Using well-mixed carbon nanotubes and adhesive polydimethylsiloxane, we fabricated an epidermal carbon nanotube electronics which maintains excellent conformal contact even within wrinkles in skin, and can be used to record electrocardiogram signals robustly. The electrode is biocompatible and can even be operated in water, which means patients can live normal lives despite wearing a complicated recording system.