Photodependent hydrogen evolution by Photosystem I entrapped in hybrid organo-silicate glasses

Photosystem I is one of the major photosynthetic energy transducing protein complexes found in the thylakoids of higher plants, cyanobacteria, and algae. Its primary function is to convert light into the electrochemical energy required for metabolic cellular processes. As a molecular photovoltaic structure, it is capable of generating a 1 v potential over a 6 nm distance after absorption of a photon. The immobilization and stabilization of PSI in a solvent-limited and optically clear organo-silicate glass was studied. The protein retained its activity during the immobilization procedure and after 96 wt % of the solvent was removed. The functionality of the immobilized protein was demonstrated by its ability to catalyze photo-dependent hydrogen evolution. The ability to manipulate PSI in a solid-state environment was essential for the exploitation of its unique optoelectronic properties for photofuel cells, photovoltaics, and other bioelectronics applications. This is an abstract of a paper presented at the 230th ACS National Meeting (Washington, DC 8/28/2005-9/1/2005).