Copper Oxide Nanotube Arrays Produced by MOCVD Process with Template

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optical properties, which allowed us to use a specialized microscope tuned to the near-infrared to pinpoint their locations within the cells.” Weisman, Paul Cherukuri of the Texas Heart Institute, and their colleagues reported their research in the December 8, 2004, issue of the Journal of the American Chemical Society (p. 15638; doi: 10.1021/ja0466311). The researchers cultured mouse macrophage cells in solutions containing between 0 ppm and 7 ppm single-walled carbon nanotubes (SWNTs) for periods of up to 96 h. They found that the amount of SWNTs taken up by the cells increased smoothly as the concentration or the time of exposure increased. In addition, some cells cultured at cooler temperatures showed a slower rate of uptake, a finding that suggested that the nanotubes were being ingested through normal phagocytosis. The samples were studied using a spectrofluorometer and a fluorescence microscope that was modified for near-infrared imaging by the addition of a digital camera containing InGaAs detector elements. Not only did the nanotubes retain their optical signatures after entering the white blood cells, but the introduction of nanotubes caused no measurable change in cell properties like shape, rate of growth, or the ability to adhere to surfaces. The new findings demonstrate that SWNTs might be valuable biological imaging agents, in part because SWNTs fluoresce in the near-infrared portion of the spectrum, at wavelengths not normally emitted by biological tissues. This may allow light from even a handful of nanotubes to be selectively detected from within the body. This option may prove particularly beneficial in cases where the bleaching, toxicity, and degradation of more traditional markers are problematic.

tions in devices containing copper oxide thin films or as cathode materials in lithium copper oxide electrochemical cells. In the December 28, 2004, issue of Chemistry of Materials (p. 5559; doi: 10.1021/cm048685f), researchers from Università di Catania in Italy announced that they have grown homogeneous CuO nanotube arrays on a template by MOCVD. G. Malandrino of Università di Catania and colleagues used anodic aluminum oxide membranes as a template. The 60-µm-thick template consists of a precise, non-deformable structure, with pores 200 nm in diameter arranged in a a

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Copper Oxide Nanotube Arrays Produced by MOCVD Process with Template Because of the tremendous improvement in chemical properties resulting from the incorporation of nanostructured materials, inorganic nanostructures have been extensively studied for applications such as electrical contacts, catalytic gassensing devices, and solar cells. Various techniques, including metalorganic chemical vapor deposition (MOCVD), have been attempted for synthesizing inorganic (metal, oxide, halide, and chalcogenide) nanotubes or nanowires. Researchers are now trying to achieve the synthesis of CuO nanotubes by a simple and reproducible method using a so-called “t

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