Miniaturized additively manufactured co-laminar microfluidic glucose biofuel cell with optimized grade pencil bioelectrodes

Miniaturization of enzymatic biofuel cell has become a crucial factor especially towards device fabrication and integrated bioelectrode system. When successful in a cost-effective manner, it can be used as a source of qualitative electric power for portable and implantable devices. The present work demonstrates the design and fabrication of costeffective, portable, miniaturized microfluidic enzymatic biofuel cell (M-EBFC) using rapid prototyping 3D printing (3DP) technique. The low cost, radially available, non-toxic Pencil Graphite Electrodes (PGE's) were used as the electrode material. Various grades of PGE's were rigorously studied, by screening separately and cohesively for both anodic and cathodic sides, and the optimized ones (B and 5H for anodic and cathodic sides respectively) have been utilized. These PGE's successively encapsulated into Y-shaped microchannel, fabricated using a commercial 3D Printer. This platform, integrating 3D printing technology and PGE's, delivers simplistic, cost-effective and quick fabrication method, which eradicates the necessity of any further amendment and post-processing. Furthermore, the enhancement of the surface area and electrochemical sensing, PGE's were coated with carboxylated multiwalled carbon nanotube followed by the covalent immobilization enzymes. The electrochemical and polarization performance was compared between both HB and the optimized PGEs. The optimized PGE based 3D printed microfluidic membraneless enzymatic biofuel cell (3DP-MM-EBFC) showed open circuit potential (OCP) of 0.433 V and with a maximum power density of 18 mu W cm(-2) at a current density of 60 mu A cm(-2). This rapidly prototyped 3D printed fabrication technology demonstrates the viability of simple and advanced microfabrication techniques to build well-organized plugand-play devices to power several portable low-power microelectronic devices and sensors. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.