title: Photocurrent generation from surface assembled photosystem I on alkanethiol modified electrodes.
abstract: Photosystem I (PSI) is a key component of oxygenic photosynthetic electron transport because of its light-induced electron transfer to the soluble electron acceptor ferredoxin. This work demonstrates the incorporation of surface assembled cyanobacterial trimeric PSI complexes into a biohybrid system for light-driven current generation. Specifically, this work demonstrates the improved assembly of PSI via electrophoretic deposition, with controllable surface assembled PSI density, on different self-assembled alkanethiol monolayers. Using artificial electron donors and acceptors (Os(bpy)(2)Cl(2) and methyl viologen) we demonstrate photocurrent generation from a single PSI layer, which remains photoactive for at least three hours of intermittent illumination. Photoelectrochemical comparison of the biohybrid systems assembled from different alkanethiols (hexanethiol, aminohexanethiol, mercaptohexanol, and mercaptohexanoic acid) reveals that the PSI generated photocurrent is enhanced by almost 5 times on negatively charged SAM surfaces as compared to positively charged surfaces. These results are discussed in light of how PSI is oriented upon electrodeposition on a SAM.
authors: Sensors and Electron Devices Directorate, United States Army Research Laboratory, Adelphi, Maryland 20783, United States.
authors: Amy K
authors: AK
authors: Manocchi
authors: David R
authors: DR
authors: Baker
authors: Scott S
authors: SS
authors: Pendley
authors: Khoa
authors: K
authors: Nguyen
authors: Margaret M
authors: MM
authors: Hurley
authors: Barry D
authors: BD
authors: Bruce
authors: James J
authors: JJ
authors: Sumner
authors: Cynthia A
authors: CA
authors: Lundgren
mesh_terms: D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D010777:Photochemistry / Q000379:methods*; D045331:Photosystem I Protein Complex / Q000737:chemistry*
chemical_list: D045331:Photosystem I Protein Complex