3D Direct-Ink-Writing Eutectogel with Programmable Architecture for Multimodal Wearable Interfaces in Personalized Rehabilitation.

Here, we report a 3D-printable eutectogel with programmable architectures for multimodal rehabilitation interfaces. The eutectogel is fabricated via polymerization of acrylamide in a ternary deep eutectic solvent, with carbomer and carbon nanotubes incorporated to optimize the rheology, mechanical robustness, and ion/electron conductive network. The optimized formulation possesses mechanical compliance, fatigue resistance, high conductivity, and antifreezing/dehydration properties, while it supports high-fidelity 3D direct ink writing. By programming device architectures, the eutectogel is printed into capacitive pressure sensors, resistive strain sensors, and a Morse-Code touch interface. The pressure sensor shows a sensitivity of 1.01 kPa-1, a detection limit of 29 Pa, and a range of ∼1 MPa, while the strain sensor achieves a gauge factor of 2.17. The eutectogel can also function as a bioelectrode for stable electromyography and electrocardiography signals acquisition. These integrated modules enable motion tracking, physiological monitoring, and active emergency feedback for personalized rehabilitation.