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Liquid-metal crosslinked hydrogel enables durable wearable sensors
Researchers have developed a high-strength conductive hydrogel based on a deep eutectic solvent and liquid metal nanoparticles. The material combines mechanical robustness, anti-drying and freezing resistance, antibacterial activity and reliable strain-sensing performance for flexible electronics.
Conductive hydrogels are promising candidates for biosensors, bionic robotics and intelligent sensing applications, yet conventional formulations often suffer from limited mechanical strength, poor toughness and insufficient resistance to drying and freezing. A research team has now developed a hydrogel system that overcomes these limitations by combining a deep eutectic solvent (DES) with liquid metal as both initiator and crosslinker.
The preparation begins with Tween-20-assisted high-speed homogenisation to disperse liquid metal nanoparticles (LMNPs) in a choline chloride-glycerol DES. Acrylic acid and acrylamide are then added, and ultrasonic treatment triggers liquid-metal-initiated radical polymerisation, yielding a double-network Gel-LM-PVA-P(AA-co-AM) hydrogel.
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Mechanical robustness and environmental stability
The resulting material exhibits a fracture stress of 1.34 MPa, a fracture strain of 517 %, a toughness of 5.68 MJ/m³ and a Young’s modulus of 1.2 MPa, alongside notable fatigue resistance. The deep eutectic solvent matrix provides effective anti-drying performance and freezing resistance, addressing two of the main durability concerns associated with traditional water-based hydrogels operating under variable environmental conditions.
Conductivity and sensing performance
Beyond mechanical performance, the hydrogel demonstrates antibacterial activity and an electrical conductivity of 0.30 mS/cm. It enables rapid, sensitive and stable strain-sensing responses to diverse human motions. According to the authors, the combination of high mechanical strength, environmental robustness and reliable signal transduction positions this DES-based hydrogel as a candidate for next-generation flexible electronics and wearable devices.
Source: Wang, J. et al., High-strength, anti-drying and freezing-resistant conductive hydrogels based on deep eutectic solvents. Progress in Organic Coatings (2026), https://doi.org/10.1016/j.porgcoat.2026.110055.
