Hydrogel Patterning with Catechol Enables Networked Electron Flow

Reduction–oxidation (redox) reactions provide a distinct modality for biological communication that is fundamentally different from the more‐familiar ion‐based electrical modality. Biology uses these two modalities for communication through different systems (immune versus nervous), and uses different mechanisms to control the flow of the charge carriers: the flow of soluble ions is controlled using structural barriers (i.e., membranes) and...