Network-based redox communication between abiotic interactive materials

Jinyang Li; Zhiling Zhao; Eunkyoung Kim; John R Rzasa; Guanghui Zong; Lai-Xi Wang; William E Bentley; Gregory F Payne

doi:10.1016/j.isci.2022.104548

Network-based redox communication between abiotic interactive materials

iScience. 2022 Jun 7;25(7):104548. doi: 10.1016/j.isci.2022.104548. eCollection 2022 Jul 15.

Authors

Jinyang Li^{1

2}, Zhiling Zhao^{3

2}, Eunkyoung Kim^{3

2}, John R Rzasa^{1

2}, Guanghui Zong⁴, Lai-Xi Wang⁴, William E Bentley^{1

3

2}, Gregory F Payne^{3

2}

Affiliations

¹ Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
² Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, MD 20742, USA.
³ Institute for Bioscience and Biotechnology Research, University of Maryland, College Park, MD 20742, USA.
⁴ Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.

Abstract

Recent observations that abiotic materials can engage in redox-based interactive communication motivates the search for new redox-active materials. Here we fabricated a hydrogel from a four-armed thiolated polyethylene glycol (PEG-SH) and the bacterial metabolite, pyocyanin (PYO). We show that: (i) the PYO-PEG hydrogel is reversibly redox-active; (ii) the molecular-switching and directed electron flow within this PYO-PEG hydrogel requires both a thermodynamic driving force (i.e., potential difference) and diffusible electron carriers that serve as nodes in a redox network; (iii) this redox-switching and electron flow is controlled by the redox network's topology; and (iv) the ability of the PYO-PEG hydrogel to "transmit" electrons to a second insoluble redox-active material (i.e., a catechol-PEG hydrogel) is context-dependent (i.e., dependent on thermodynamic driving forces and appropriate redox shuttles). These studies provide an experimental demonstration of important features of redox-communication and also suggest technological opportunities for the fabrication of interactive materials.

Keywords: Bio-electrochemistry; Materials science; Polymers.