Voltage generation by photosystem I complexes immobilized onto a millipore filter under continuous illumination

• Published in: International journal of hydrogen energy 2022-03, Vol.47 (22), p.11528-11538
• Main Authors: Zaspa, Andrey, Vitukhnovskaya, Liya, Mamedova, Aida, Allakhverdiev, Suleyman I., Semenov, Alexey, Mamedov, Mahir
• Format: Article
• Language: English
• Subjects: Cytochrome c6; Indium tin oxide; Millipore filter; Photosystem I; Photovoltage; Trehalose
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2022.01.175

Here we measured the long-term photovoltage (ΔV) generation by photosynthetic pigment-protein complex of photosystem I (PS I) from cyanobacterium Synechocystis sp. PCC 6803 directly. Prior to measurements PS I was immobilized onto a Millipore membrane filter (MF) and sandwiched between two semiconductor indium tin oxide (ITO) electrodes. The ability of ITO|PS I-MF|ITO system to generate a stable ΔV over a 50 min period of irradiation by white light was detected in the presence of cytochrome c6, methyl viologen and disaccharide trehalose. Re-injection of a fresh buffer into ITO|PS I-MF|ITO preserves the immobilized PS I functionality after six months of storage at 23 °C in the dark. The developed system represents a simple bio-hybrid solar converter to obtain voltage signals under long-term, periodic illumination. This approach can also be used to couple photoactive (light-driven enzymes) and catalytic modules to generate H2 under the steady-state conditions. [Display omitted] •PS I immobilization onto a Millipore nitrocellulose membrane.•Direct measurement of photovoltage in PS I using semi-conductors.•Generation of a stable voltage over a 50 min period of irradiation.•Preservation of PS I photoactivity after 6 months storage at 23 °C in the dark.