Towards a Biomineralized Photocatalyst: Identification of a ZnO-binding Peptide
Authors:Marzieh FanaeianSeyediTousi, Chung Hee Moon, Mohammad Shahriar Zaman
Mentor:Elaine Haberer, Assistant Professor, Electrical Engineering Department, Material Science and Engineering Program, University of California Riverside
Clean air and water are important for sustainable habitats. Photocatalysis can be used to remove toxic molecules and pollutants such as insecticides, phenol, and carcinogenic species from air and water. Photocatalysis uses solar energy to activate a photosensitive material which catalyzes the chemical reactions necessary for degradation of pollutants. Biomineralized nanostructured ZnO is a semiconductor material with suitable optical and electrical properties for photocatalysis, as well as a high surface area for enhanced chemical reactions. Furthermore, unlike many conventional methods, biomineralized ZnO is manufactured under ambient conditions in aqueous solution. The immediate goal of this project was to find a specific peptide that binds to ZnO and may be used to biomineralize nanostructures of ZnO in the future. Biopanning was used to identify peptides that bind to ZnO. This evolutionary technique began with a combinatorial library with approximately 107 possible binding peptides. After five rounds of biopanning, only the phages displaying peptides with strong affinity to ZnO were collected. The ZnO-binding peptide found in this study was VPGAAEHT which appeared 7 times out of the 23 (more than 30 percent) randomly picked sequences at the end of the fifth round of biopanning. Binding studies were completed with this peptide and it was shown to bind ZnO more times than a control peptide. Solar energy is cheap and plentiful, and photocatalysis is cheap and abundant. This research could be helpful for future studies on photocatalysis and purification of air and water treatment.