# EGaIn‐Activated Bioinspired Silk Micro/Nanofibril Eutectogels Breaking the Strength–Conductivity Trade‐Off for High‐Performance Wearable Bioelectronics

## TL;DR

This paper introduces a new type of eutectogel inspired by biological structures, which is strong, tough, and conductive, making it ideal for wearable bioelectronics.

## Contribution

A bioinspired strategy using silk micro/nanofibrils and EGaIn enables eutectogels that break the strength–conductivity trade-off.

## Key findings

- The eutectogel achieves a tensile strength of 1.25 MPa and conductivity of 1.51 S m⁻¹.
- It exhibits toughness of 23.09 MJ m⁻³ and fracture strain of 2289%.
- The material enables ultrasensitive strain sensing and stable bioelectrical signal monitoring.

## Abstract

Eutectogels combining high mechanical and electrical performance hold great promise for next‐generation wearable electronics. However, conventional polymerizable deep eutectic solvent (PDES)–based eutectogels suffer from an inherent strength–conductivity trade‐off. Here, inspired by the multiscale architecture of the extracellular matrix, a bioinspired strategy is developed by integrating silk micro/nanofibrils (SMNF) as a reinforcing scaffold within a choline chloride/acrylic acid PDES. SMNF are generated in situ via deconstruction of silk fibers, while eutectic gallium–indium (EGaIn) microdroplets initiate polymerization without toxic initiators or high‐energy UV irradiation, enabling one‐step fabrication of SMNF‐reinforced eutectogels (SMNF‐Egel). The resulting SMNF‐Egel combines dynamic hydrogen and coordination bonding with a robust micro/nanofibrous network, achieving a tensile strength of 1.25 MPa, toughness of 23.09 MJ m−3, fracture strain of 2289%, and conductivity of 1.51 S m−1, alongside skin‐like modulus, self‐healing, and environmental stability. These properties enable ultrasensitive strain sensing, Morse code communication, and stable bioelectrical signal monitoring. This work establishes a sustainable route to high‐performance silk‐based eutectogels and provides a versatile platform for advanced wearable sensors and bioelectronic interfaces.

Inspired by the extracellular matrix, eutectogels are prepared by in situ deconstruction of silk fibroin into micro/nanofibrils and EGaIn‐induced polymerization. The multiscale fibril network with dynamic crosslinking achieves high strength (1.25 MPa), toughness (23.09 MJ m−3), and conductivity (1.51 S m−1), outperforming previous natural polymer–reinforced eutectogels and breaking the strength–toughness–conductivity trade‐off for wearable sensors and bioelectrodes.