Interactive Materials for Bidirectional Redox-Based Communication

Adv Mater. 2021 May;33(18):e2007758. doi: 10.1002/adma.202007758. Epub 2021 Mar 31.


Emerging research indicates that biology routinely uses diffusible redox-active molecules to mediate communication that can span biological systems (e.g., nervous and immune) and even kingdoms (e.g., a microbiome and its plant/animal host). This redox modality also provides new opportunities to create interactive materials that can communicate with living systems. Here, it is reported that the fabrication of a redox-active hydrogel film can autonomously synthesize a H2 O2 signaling molecule for communication with a bacterial population. Specifically, a catechol-conjugated/crosslinked 4-armed thiolated poly(ethylene glycol) hydrogel film is electrochemically fabricated in which the added catechol moieties confer redox activity: the film can accept electrons from biological reductants (e.g., ascorbate) and donate electrons to O2 to generate H2 O2 . Electron-transfer from an Escherichia coli culture poises this film to generate the H2 O2 signaling molecule that can induce bacterial gene expression from a redox-responsive operon. Overall, this work demonstrates that catecholic materials can participate in redox-based interactions that elicit specific biological responses, and also suggests the possibility that natural phenolics may be a ubiquitous biological example of interactive materials.

Keywords: catechols; electro-biofabrication; extracellular electron transfer; interactive materials; redox signaling.

MeSH terms

  • Catechols / metabolism
  • Electron Transport*
  • Escherichia coli / metabolism


  • Catechols
  • catechol