Peptide-enhanced tough, resilient and adhesive eutectogels for highly reliable strain/pressure sensing under extreme conditions

Biomimetic hydrogel materials show outstanding mechanical properties but water as solvent or carrier limits the possibility to apply these materials under extreme conditions. Here the authors report a peptide-enhanced eutectogel with excellent mechanical, anti-freezing and anti-drying properties and its application as sensor for monitoring human motion. Natural gels and biomimetic hydrogel materials have been able to achieve outstanding integrated mechanical properties due to the gain of natural biological structures. However, nearly every natural biological structure relies on water as solvents or carriers, which limits the possibility in extreme conditions, such as sub-zero temperatures and long-term application. Here, peptide-enhanced eutectic gels were synthesized by introducing alpha-helical "molecular spring" structure into deep eutectic solvent. The gel takes full advantage of the alpha-helical structure, achieving high tensile/compression, good resilience, superior fracture toughness, excellent fatigue resistance and strong adhesion, while it also inherits the benefits of the deep eutectic solvent and solves the problems of solvent volatilization and freezing. This enables unprecedentedly long and stable sensing of human motion or mechanical movement. The electrical signal shows almost no drift even after 10,000 deformations for 29 hours or in the -20 degrees C to 80 degrees C temperature range.