10-04 :: April 2010
nanotimes
News in Brief
47
Bioelectricity //
Researchers Find Electrical Current Stemming From Plants
In an electrifying first, Scientists from Stanford
University, USA, and Yonsei University, Republic of Korea, have plugged in to algae cells and har- nessed a tiny electric current. They found it at the
very source of energy production – photosynthesis, a plant‘s method of converting sunlight to chemical energy. The Stanford research team developed a unique, ultra-sharp nanoelectrode made of gold, spe- cially designed for probing inside cells. They gently pushed it through the algal cell membranes, which sealed around it, and the cell stayed alive. From the photosynthesizing cells, the electrode collected electrons that had been energized by light and the researchers generated a tiny electric current.
“We believe we are the first to extract electrons out of living plant cells,” said WonHyoung Ryu, the lead author of the paper. Ryu conducted the experiments while he was a research associate for mechanical engineering professor Fritz Prinz. “We‘re still in the scientific stages of the research,” said Ryu. “We were dealing with single cells to prove we can harvest the electrons.”
In this experiment, the researchers intercepted the electrons just after they had been excited by light and were at their highest energy levels. They placed the gold electrodes in the chloroplasts of algae cells, and siphoned off the electrons to generate the tiny
electrical current. The result, the researchers say, is electricity production that doesn‘t release carbon into the atmosphere. The only byproducts of photo- synthesis are protons and oxygen.
“This is potentially one of the cleanest energy sources for energy generation,” Ryu said. “But the question is, is it economically feasible?”
Ryu said they were able to draw from each cell just one picoampere, an amount of electricity so tiny that they would need a trillion cells photosynthesi- zing for one hour just to equal the amount of energy stored in a AA battery. In addition, the cells die after an hour. Ryu said tiny leaks in the membrane around the electrode could be killing the cells, or they may be dying because they‘re losing out on energy they would normally use for their own life processes. One of the next steps would be to tweak the design of the electrode to extend the life of the cell, Ryu said.
WonHyoung Ryu, Seoung-Jai Bai, Joong Sun Park, Zubin Huang, Jeffrey Moseley, Tibor Fabian, Rainer J. Fasching, Arthur R. Grossman and Fritz B. Prinz: Direct Extraction of Photosynthetic Electrons from Single Algal Cells by Nano- probing System, In: Nano Letters, Vol. 10(2010), Issue 4, April 14, 2010, Pages 1137-1143, DOI:10.1021/ nl903141j:
http://dx.doi.org/10.1021/nl903141j
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87