Xurography for 2D and multi-level glucose/O2 microfluidic biofuel cell

This work reports on a simple and original method for constructing a multi-level microfluidic biofuel cell (BFC) by using the xurography technique. Microfluidic BFCs have attractive properties for converting chemical energy into electrical energy via specific enzymes as catalysts and are now considered as microsources able to supply power for portable electronic systems. As a proof-of-concept demonstration, we construct 2D and multi-level microfluidic BFCs that consist of an array of microchannels and gold electrodes designed in series or parallel configuration, and we demonstrate its operation from glucose and oxygen solutions. The fabrication process of the multi-level microfluidic device involves the stacking of alternating layers of double-sided adhesive tape and transparent sheets patterned with holes to provide connections between the channels. This process of stacking provides a reproducible method for building devices with a distribution of the fluids both vertically and laterally without mixing. The efficiency of the multi-level microfluidic device is confirmed in the presence of the enzymes laccase and glucose oxidase in solution. The proposed technique offers an alternative to construct microfluidic BFCs that deliver power output in a minimum volume, favorable to scale-up the manufacture of compact micropower sources.