PDMS-Based Microfluidic Glucose Biofuel Cell Integrated With Optimized Laser-Induced Flexible Graphene Bioelectrodes

Abstract

Development of economical and mass-manufacturable bioelectrodes with desirable physical properties is one of the crucial challenges to realize automated and robust enzymatic biofuel cell (EBFC). This article focuses to develop customized CO2 laser-induced flexible graphene (LIFG) bioelectrodes on the polyamide substrate. The cost-efficiency and customization of LIFG bioelectrodes have been further demonstrated for EBFC application by integrating them into a microfluidic device, fabricated by the conventional soft lithography on polydimethylsiloxane (PDMS). First, the LIFG bioelectrodes were created at optimized CO2 laser (power and speed) irradiation, and characterization was performed to ensure the existence of graphene material. Subsequently, the surface morphological study of the noninduced polyamide sheet, LIFG, and LIFG with the relevant enzyme (GOx and laccase)-modified bioelectrodes has been characterized. Finally, various voltammetric electrochemical analyses of the modified LIFG bioelectrodes have been accomplished. After such an electrochemical study, the bioelectrodes were integrated into the microfluidic device and a power density of 13 μW/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> (52 μA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ) was harnessed at an optimized fluid rate of 200 μL/min. By using this fabrication method, the proposed LIFG bioelectrodes have shown excellent potential for electrochemical redox and polarization performance in a microfluidic environment, with a huge scope to enrich the power output by introducing the additional cofactor-based electrochemistry and device stacking.