Interfacing photosynthetic enzymes and bacteria with electrodes for bio-optoelectronic devices

Photosynthetic microorganisms and their Reaction Center (RC) photoenzymes can be used as active materials for bio-optoelectronic applications. Here we report approaches to interface RC molecules extracted from Rhodobacter sphaeroides with electrodes aiming to integrate the RC in electronic and electrochemical devices. Covalent binding with molecular semiconductors or supramolecular organization based on selective interactions have been explored. Alternatively, entrapment of the RC in biocompatible polymers is a convenient approach. These soft structures include polydopamine-based films or polydopamine/ethylenediamine nanoparticles capable of confining and protecting the RC, while improving RC-electrode charge transfer. We also describe the use of these polymers to address living photosynthetic bacterial cells on electrodes.