A paper-based 3D sensor array for electromicrobiology

In this work, we provided a strategy for high-throughput monitoring of temporal and spatial gradients of electrons/protons in electrogenic bacterial biofilms by utilizing 3D multi-laminate structures of paper as a scaffold to support bacterial biofilms and/or media. Assembly of a 3D paper stack can be modular and allows us to control the thickness of the overall biofilm construct and diffusion of nutrients/redox mediators through the stack and the shapes of gradients in the stacks can be modulated by changing the composition of each layer. By measuring the current generated from different stack configurations, the electron/proton fluxes through biofilms were quantitatively investigated.