One-step synthesis of MXene-functionalized PEDOT:PSS conductive polymer hydrogels for wearable and noninvasive monitoring of sweat glucose

Wearable biosensors have gained substantial attention for their capacity to deliver real-time and continuous physiological information through noninvasive and dynamic monitoring of biochemical markers in biological fluids. In particular, wearable and flexible electrochemical sensors have found extensive usage for the detection of biomarkers in human sweat in a quantifiable and noninvasive manner. Herein, we present a novel MXene-functionalized PEDOT:PSS conducting composite hydrogels-based electrochemical biosensor for continuous noninvasive monitoring of human glucose. Ethylene glycol (EG) was added to the hydrogel throughout the preparation process, aiding in the expansion of the polymer chains and resulting in excellent electrical conductivity and porous networks, which helps to increase the film-forming properties, flexibility and stability of the material, and also improves the stacking and peeling problems of powdered materials. The limit of the hydrogel biosensor for glucose detection was as low as 1.9 μM and the sensitivity was 21.7 μA⋅mM−1⋅cm−2. Furthermore, the hydrogel incorporated with screen-printed carbon electrodes (SPCE) was employed to the human body for continuous noninvasive sweat glucose monitoring as the skin patch in vitro. The results of the biosensor showed good correlation with glucose meter readings. We believe that this glucose biosensor lays the foundation for noninvasive wearable monitoring of glucose in diabetic patients.