Ultrastretchable, repairable and highly sensitive xanthan collagen nanosilver hydrogel for wide temperature flexible sensing

Abstract

Conductive hydrogels, lauded for their electrical conductivity, precise information capture, biocompatibility, and extensibility, have gained prominence as ideal candidate materials for flexible wearable sensor applications. Nevertheless, these sensors must surmount numerous challenges such as environmental temperature variations, bacterial growth in high-humidity environments, low signal detection sensitivity, irreversible damage, and mechanical performance stability during use. In response to these challenges, we present a hydrophobic supramolecular and dynamic coordination double-network hydrogel, prepared through a solvent-exchange method, with an accelerated gelation rate. The coordination of dynamic hydrogen bonds and coordination bonds within the hydrophobic supramolecular network imbues the hydrogel with superior mechanical properties (elongation at break around 4900%, tensile strength approximately 506 kPa) and improved self-healing capabilities. This solvent-exchange-mediated hydrogel exhibits broad temperature resilience (−20–60 °C) and reliable repeatability. Additionally, the sensor enables wireless human signal monitoring with a rapid response time (75 ms) and heightened sensitivity (gauge factor = 22.34). The wearable sensor’s antibacterial efficacy effectively suppresses bacterial propagation in high-moisture hydrogels, with a bacterial inhibition rate of 99.9%. The findings from our series of studies reveal the successful fabrication of stable, flexible wearable sensors with self-healing, antibacterial, high sensitivity, and broad temperature tolerance characteristics, showcasing the immense potential for applications in wearable electronics, wireless monitoring, and human–machine interactions.