Mechanically Reinforced Nanocomposite Hydrogels and Advanced Applications in Biosensing and Bioelectronics

Nanocomposite hydrogels, as emerging multifunctional and flexible materials, have garnered significant attention in biosensing and bioelectronic applications due to their outstanding mechanical properties and diverse functional features. By integration of nanomaterials with hydrogel matrices, the mechanical properties are significantly enhanced while their softness and high-water content are maintained, making them particularly suitable for applications in flexible sensors, artificial muscles, and tissue engineering. This Review summarizes the latest advancements in nanocomposite hydrogels, with a focus on the mechanisms and effects of mechanical property enhancement as well as the characteristics of interactions between hydrogel matrices and nanomaterials. The applications in biosensors and bioelectronic devices are also discussed. There are four types of nanofillers included: polymeric nano/microgels, carbon-based nanoparticles, silicon-based nanoparticles, and metallic or metal oxide nanoparticles. Representative case studies are carefully selected, with a detailed discussion of their fabrication methods, mechanical enhancements, advantages, and limitations. Finally, the prospects and challenges of nanocomposite hydrogels in biosensor and wearable device applications are explored.