Biocompatible material

Fabrication

Nanomaterials

Pathology

Nanotechnology

Printed electronics

Inkwell

Wearable computer

Biomedical engineering

Electronics

Physical chemistry

Embedded system

Composite material

Chemistry

Materials science

Alternative medicine

Sericin

SILK

Computer science

Wearable technology

Carbon nanotube

Medicine

Advanced Materials

Ink‐based processes, which enable scalable fabrication of flexible devices based on nanomaterials, are one of the practical approaches for the production of wearable electronics. However, carbon nanotubes (CNTs), which possess great potential for flexible electronics, are facing challenges for use in inks due to their low dispersity in most solvents and suspicious cytotoxicity. Here, a stable and biocompatible CNT ink, which is stabilized by sustainable silk sericin and free from any artificial chemicals, is reported. The ink shows stability up to months, which can be attributed to the formation of sericin–CNT (SSCNT) hybrid through non‐covalent interactions. It is demonstrated that the SSCNT ink can be used for fabricating versatile circuits on textile, paper, and plastic films through various techniques. As proofs of concept, electrocardiogram electrodes, breath sensors, and electrochemical sensors for monitoring human health and activity are fabricated, demonstrating the great potential of the SSCNT ink for smart wearables.

Stable and Biocompatible Carbon Nanotube Ink Mediated by Silk Protein for Printed Electronics