Viologen‑modified redox polymer electrodes

Viologen‑modified redox polymer electrodes are electrochemical interfaces where polymer matrices containing viologen groups are deposited on conductive substrates to mediate electron transfer and control local redox conditions, particularly useful for interfacing and protecting sensitive enzymes or cells.[1][2] In the cyanobacterial hydrogen system, such a polymer layer holds the cells close to the electrode and contains viologen moieties that can be electrochemically reduced to efficiently remove dissolved oxygen around the cells, thereby creating a microenvironment compatible with oxygen‑sensitive hydrogenases.[1][2]