Patterned Nanowire Electrode Array for Direct Extraction of Photosynthetic Electrons from Multiple Living Algal Cells

Abstract

An electrochemically active nanowire system is fabricated using wet‐tapped nanosphere lithography and a single photolithography step. The patterned nanowire/nanoelectrode is inserted into live algal cells, enabling the potential harvesting of photosynthetic electrons from multiple cells simultaneously. Light‐dependent extraction of electrons from cells is observed; these electrons are derived from the photosynthetic electron transport chain based on a light intensity‐dependence of the reaction coupled with the finding that electron extraction is inhibited in the presence of DCMU (3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea), a reagent that specifically blocks electron flow out of photosystem II. Insertion of nanoelectrodes into multiple algal cells is achieved, and sequential insertion of cells with the nanoelectrode, followed by subsequent removal of the electrode, yields a corresponding increase and then decrease in light‐driven currents. Controlling the intensity of the illumination avoids nearly all photodamage and enables direct extraction of more photosynthetic electrons from multiple cells in parallel, which is sustained for an extended period of time.