Carboxymethyl Cellulose Sodium Nanocomposite Hydrogels for Flexible Sensors of Human Motion and Glucose Levels in Sweat

In recent years, there has been an increasing interest in the use of biomass-based nanocomposite hydrogels for wearable flexible sweat sensors. In this manuscript, the design of a dual-network hydrogel using sodium carboxymethyl cellulose (CMC-Na) to develop a high-performance nanocomposite hydrogel flexible sensor is considered to be an effective method for accurate monitoring of human movement and continuous noninvasive measurement of glucose levels in sweat. The gel has a measurement gauge factor (GF) of 1.34 and a toughness of 4.18 MJ/m3, exhibiting excellent mechanical properties and self-healing capabilities (92.6%). As a flexible motion sensor, it can accurately identify various human movements. By incorporating glucose oxidase-thioglycolic acid-gold nanoparticles (GTAN) nanomaterials into the hydrogel, stable and excellent electrocatalytic activity for sweat glucose measurement was achieved. The sensor has a detection limit (LOD) of 0.28 μM and a wide operating range. Additionally, different testing methods show good linear relationships, indicating the sensor's universality in measurement. By analyzing daily physical activities and levels of glucose in sweat, monitoring of individual health can be achieved, thereby expanding the potential of next-generation noninvasive multifunctional sensing systems.