A Flexible and Wearable Chemiresistive Biosensor Fabricated by Laser Inducing for Real-Time Glucose Analysis of Sweat

Abstract

In this study, a flexible and wearable chemiresistive biosensor (FWCB) is developed for the real-time analysis of glucose in sweat on the human skin surface based on a novel detection strategy of p-type reduced graphene oxide (rGO) sensing film, which met the requirements of rapid, nondestructive testing. The proposed FWCB is fabricated in the form of interdigital electrodes (IEs) made of laser-induced graphene (LIG) synthesized by the laser inducing of a polyimide (PI) film. Additionally, a semiconducting rGO sensing film modified on the surface of IEs is synthesized by thermal reduction of graphene oxide (GO), which is functionalized with glucose oxidase (GOx) by chemical cross-linking to obtain GOx/FWCB. Moreover, the key parameters for FWCB fabrication are optimized, and the sensing strategy of the proposed GOx/FWCB is also investigated. The results show that the proposed GOx/FWCB can be used for the detection of glucose in the range of 0.01–3.0 mM with satisfactory selectivity, and the limit of detection (LOD) is calculated to be as low as 0.8 µM (S/N = 3). These dramatic advantages endow the proposed FWCB with broad application prospects in the field of portable, wearable, and real-time detection of glucose in human sweat for health monitoring.