Extracting Photosynthetic Electrons from Thylakoids on Micro Pillar Electrode

Extraction of photosynthetic currents from thylakoids was studied using micro pillar structured electrode. Thylakoids were isolated from spinach leaves, and the size and shape of thylakoids were estimated from scanning electron microscopy images. Based on the geometry information of thylakoids, micro pillar shaped electrode was designed and fabricated using metal-assisted chemical etching of silicon wafers. Influence of photovoltaic effect on the silicon-based micro pillar electrode was confirmed to be negligible. Photosynthetic currents were measured in a three-electrode setup with an electron mediator, potassium ferricyanide. Photosynthetic currents from micro pillar electrodes were enhanced compared with the currents from flat electrodes. This indicates the significance of the enhanced contact between thylakoids and an electrode for harvesting photosynthetic electrons.