10-04 :: April 2010

nanotimes

News in Brief

damage to tissue being imaged. Another advantage is that it does not produce a background „auto fluorescent“ glow of surrounding tissues, which interferes with the imaging and reduces contrast and brightness, said Ji-Xin Cheng (pronounced Gee-Shin), an associate professor of biomedical engineering and chemistry at Purdue University.

“This lack of background fluorescence makes the images much more clear and is very important for disease detection,” he said. “It allows us to clearly identify the nanocages and the tissues.” The gold-silver structures yielded images 10 times brighter than other experimental imaging research using gold nanospheres and nanorods. The ima- ging technology provides brightness and contrast potentially hundreds of times better than conven- tional fluorescent dyes used for a wide range of biological imaging to study the inner workings of cells and molecules.

Ling Tong, Claire M. Cobley, Jingyi Chen, Younan Xia, Ji- Xin Cheng: Bright Three-Photon Luminescence from Gold/ Silver Alloyed Nanostructures for Bioimaging with Negli- gible Photothermal Toxicity (p NA), In: Angewandte Che-

mie International Edition, Early View, April 6 2010, DOI:

10.1002/anie.201000440: http://dx.doi.org/10.1002/anie.201000440

Ji-Xin Cheng:

https://engineering.purdue.edu/BME/Research/Labs/Cheng

Weldon School of Biomedical Engineering:

http://www.purdue.edu/bme

Younan Xia:

http://engineering.wustl.edu/facultybio.aspx?faculty=137

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This composite image shows luminous nanocages, which appear like stars against a black background, and a living cell, at upper left. The gold-silver nanocages exhibit a bright „three-photon luminescence“ when excited by the ultrafast pulsed laser, with 10-times greater intensity than pure gold or silver nanoparticles. The signal allows live cell imaging with negligible damage from heating. © Purdue University graphic/Ji-Xin Cheng

Physicists at Harvard University, USA, have found

that a high-voltage nanotube can cause cold atoms to spiral inward under dramatic accelera- tion before disintegrating violently. Their expe-

riments, the first to demonstrate something akin to a black hole at atomic scale, are described in the current issue of the journal Physical Review Letters. “On a scale of nanometers, we create an inexo- rable and destructive pull similar to what black holes exert on matter at cosmic scales,” says Lene Vestergaard Hau, Mallinckrodt Professor of Physics 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