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Studies from University of California Further Understanding of Nanotechnology (Photoenhanced Electrochemical Interaction between Shewanella and a...

July 16, 2014

Studies from University of California Further Understanding of Nanotechnology (Photoenhanced Electrochemical Interaction between Shewanella and a Hematite Nanowire Photoanode)

By a News Reporter-Staff News Editor at Biotech Week -- A new study on Nanotechnology is now available. According to news reporting out of Santa Cruz, California, by NewsRx editors, research stated, "Here we report the investigation of interplay between light, a hematite nanowire-arrayed photoelectrode, and Shewanella oneidensis MR-1 in a solar-assisted microbial photoelectrochemical system (solar MPS). Whole cell electrochemistry and microbial fuel cell (MFC) characterization of Shewanella oneidensis strain MR-1 showed that these cells cultured under (semi)anaerobic conditions expressed substantial c-type cytochrome outer membrane proteins, exhibited well-defined redox peaks, and generated bioelectricity in a MFC device."

Our news journalists obtained a quote from the research from the University of California, "Cyclic voltammogram studies of hematite nanowire electrodes revealed active electron transfer at the hematite/cell interface. Notably, under a positive bias and light illumination, the hematite electrode immersed in a live cell culture was able to produce 150% more photocurrent than that in the abiotic control of medium or dead culture, suggesting a photoenhanced electrochemical interaction between hematite and Shewanella. The enhanced photocurrent was attributed to the additional redox species associated with MR-1 cells that are more thermodynamically favorable to be oxidized than water. Long-term operation of the hematite solar MPS with light on/off cycles showed stable current generation up to 2 weeks. Fluorescent optical microscope and scanning electron microscope imaging revealed that the top of the hematite nanowire arrays were covered by a biofilm, and iron determination colorimetric assay revealed 11% iron loss after a 10-day operation. To our knowledge, this is the first report on interfacing a photoanode directly with electricigens in a MFC system."

According to the news editors, the research concluded: "Such a system could open up new possibilities in solar-microbial device that can harvest solar energy and recycle biomass simultaneously to treat wastewater, produce electricity, and chemical fuels in a self-sustained manner."

For more information on this research see: Photoenhanced Electrochemical Interaction between Shewanella and a Hematite Nanowire Photoanode. Nano Letters, 2014;14(6):3688-3693. Nano Letters can be contacted at: Amer Chemical Soc, 1155 16TH St, NW, Washington, DC 20036, USA. (American Chemical Society -; Nano Letters -

Our news journalists report that additional information may be obtained by contacting F. Qian, University of California, Dept. of Chem & Biochem, Santa Cruz, CA 95064, United States. Additional authors for this research include H.Y. Wang, Y.C. Ling, G.M. Wang, M.P. Thelen and Y. Li (see also Nanotechnology).

Keywords for this news article include: Chemistry, Santa Cruz, California, United States, Nanotechnology, Electrochemical, North and Central America

Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC

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Source: Biotech Week

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