A sample-to-answer, wearable cloth-based electrochemical sensor (WCECS) for point-of-care detection of glucose in sweat

Wearable electrochemical (EC) biosensors have attracted tremendous attention for noninvasive diagnosis and point-of-care testing (POCT) of individual health level. The analysis of glucose concentration in epidermal sweat presents a promising means of noninvasive continuous glucose monitoring for diabetes mellitus. The previous focus has been mainly on pursuing novel EC sensing materials to achieve highly sensitive biosensors. In this work, a novel flexible three-dimensional (3-D) wearable cloth-based EC sensor (WCECS) has been proposed for analysis of glucose in sweat. The WCECS possesses excellent sweat collection channels and cloth-based sweat transport channel. Notably, the transport channel is actuated by the capillary force to absorb the sweat into the cloth-based chip which can be easily and inexpensively fabricated by the screen-printing technology. Under optimized conditions, the WCECS can well measure the concentrations of glucose in sweat over the range of 0.05-1 mM, with an acceptable sensitivity of 105.93 mu A mM-1 cm-2. Besides, the WCECS exhibits excellent selectivity, reproducibility and stability. Importantly, the EC responses of the WCECS have a good correlation with those of the glucometer, and are consistent with the results by the glucose kit. Moreover, the WCECS can be applied for constant 9 h wearable monitoring, and for simultaneous detection of lactic acid and glucose in sweat. So, the proposed approach may represent an important step toward the promising application of the cloth-based sensor for daily personalized health monitoring.