A Highly Stretchable, Conductive, and Transparent Bioadhesive Hydrogel as a Flexible Sensor for Enhanced Real-Time Human Health Monitoring

Real-time continuous monitoring of non-cognitive markers is crucial for the early detection and management of chronic conditions. Current diagnostic methods are often invasive and not suitable for at-home monitoring. An elastic, adhesive, and biodegradable hydrogel-based wearable sensor with superior accuracy and durability for monitoring real-time human health is developed. Employing a supramolecular engineering strategy, a pseudo-slide-ring hydrogel is synthesized by combining polyacrylamide (pAAm), beta-cyclodextrin (beta-CD), and poly 2-(acryloyloxy)ethyltrimethylammonium chloride (AETAc) bio ionic liquid (Bio-IL). This novel approach decouples conflicting mechano-chemical effects arising from different molecular building blocks and provides a balance of mechanical toughness (1.1 x 106 Jm-3), flexibility, conductivity (approximate to 0.29 S m-1), and tissue adhesion (approximate to 27 kPa), along with rapid self-healing and remarkable stretchability (approximate to 3000%). Unlike traditional hydrogels, the one-pot synthesis avoids chemical crosslinkers and metallic nanofillers, reducing cytotoxicity. While the pAAm provides mechanical strength, the formation of the pseudo-slide-ring structure ensures high stretchability and flexibility. Combining pAAm with beta-CD and pAETAc enhances biocompatibility and biodegradability, as confirmed by in vitro and in vivo studies. The hydrogel also offers transparency, passive-cooling, ultraviolet (UV)-shielding, and 3D printability, enhancing its practicality for everyday use. The engineered sensor demonstratesimproved efficiency, stability, and sensitivity in motion/haptic sensing, advancing real-time human healthcare monitoring. An elastic, skin-adhesive, biocompatible, and biodegradable hydrogel-based wearable sensor has been developed for human health monitoring, inspired by pseudo-slide-ring hydrogels. This novel hydrogel-based sensor offers high accuracy and mechanical strength, 3D printability, passive cooling, UV resistance, self-healing, and durability. With tunable properties, biocompatibility, and biodegradability, the engineered hydrogel-based sensor shows significant potential for real-time healthcare monitoring in human movement and motor dysfunction applications. image