Laser-induced graphene non-enzymatic glucose sensors for on-body measurements

Biosens Bioelectron. 2021 Sep 1;193:113606. doi: 10.1016/j.bios.2021.113606. Online ahead of print.ABSTRACTNon-enzymatic glucose sensors outperform enzymatic ones in terms of cost, sensitivity, stability, and operating duration. Though highly sensitive, it is still desirable to further improve the sensitivity of non-enzymatic glucose sensors to detect a trace amount of glucose in sweat and other biofluids. Among the demonstrated effective approaches using bimetals or 3D porous structures, the porous laser-induced graphene (LIG) on flexible polymers showcases good conductivity and a simple fabrication process for the integration of sensing materials. The uniform electroless plating of the nickel and gold layer on LIG electrodes demonstrates significantly enhanced sensitivity and a large linear range for glucose sensing. The sensor with the porous LIG foam exhibits a high sensitivity of 1080 μA mM-1 cm-2, whereas a further increased sensitivity of 3500 μA mM-1 cm-2 is obtained with LIG fibers (LIGF). Impressively, a large linear range (0-30 mM) can be achieved by changing the bias voltage from 0.5 to 0.1 V due to the Au coating. Because the existing non-enzymatic glucose sensors are limited to use in basic solutions, their application in wearable electronics is elusive. In addition to the reduced requirement for the basic solution, this work integrates a porous encapsulating reaction cavity containing alkali solutions with a soft, skin-interfaced microfluidic component to pro...

Source: Biosensors and Bioelectronics - September 10, 2021 Category: Biotechnology Authors: Jia Zhu Shangbin Liu Zhihui Hu Xianzhe Zhang Ning Yi Kairui Tang Michael Gregory Dexheimer Xiaojun Lian Qing Wang Jian Yang Jennifer Gray Huanyu Cheng Source Type: research