Cellulose nanocomposite hydrogel-conductive, antimicrobial and high tenacity sensor for information encryption, human motion monitoring and animal behavior studies.

Conductive hydrogels have garnered significant attention in advanced applications, particularly in wearable strain sensors. Nevertheless, the challenge of fabricating wearable sensors that demonstrate both optimal mechanical properties and high conductivity persists. In this study, we successfully developed a multifunctional hydrogel sensor comprising acrylamide (AM), polyethylene glycol (PEG), and sodium carboxymethyl cellulose (CMC). The resulting hydrogel demonstrated favorable mechanical properties, electrical conductivity, adhesion, antimicrobial activity, antifreezing capability, moisture retention, fluorescence, and strain sensitivity. Notably, the sensor retains its flexibility and electrical conductivity even at -20 °C. The incorporation of doped carbon quantum dots imparts pronounced fluorescence properties to the hydrogel, facilitating clear topographical imaging and paving the way for potential applications in information encryption. The fabricated strain sensors exhibit broad applicability and high reliability in human motion monitoring, allowing for secure attachment to the human body without the need for additional adhesives. Both large movements, such as joint bending (e.g., wrists and knees), and subtle movements, such as chewing and swallowing, can be accurately monitored. Furthermore, this study aims to integrate flexible hydrogel sensor technology with pet behavior monitoring, with the objective of identifying the emotional states of dogs. The ultimate goal is to establish a novel model for animal behavior research.