BIOMOLECULAR ELECTRONICS - VECTORIAL ARRAYS OF PHOTOSYNTHETIC REACTION CENTERS

Two-dimensional vectorial arrays of functional Photosystem I reaction centers have been prepared on atomically flat derivatized gold surface s. The nature and extent of orientation were controlled by chemical mo dification of the surface derivative. For mercaptoacetic acid, 83% of the electron transport vectors were parallel to the surface, whereas w ith 2-mercaptoethanol 70% were oriented perpendicularly in the ''up'' position and only 2% were in the ''down'' position. No preferential or ientation was observed with 2-dimethylaminoethanethiol.