60

nanotimes

News in Brief

INSCX™ the Integrated Nano-Science & Com- modity Exchange has just published a major new

study entitled “Nanotechnology at a Crossroads: A Paradigm Shift for Capital Allocation” detailing

the rationale for increased collaboration between science & capital to propel forward the commer- cialization of nanomaterials and nanotechnology.

http://www.nanocentral.eu/wp-content/uploads/Nano- Crossroads.pdf

An international study based at the University of Pittsburgh, USA, provides the first identification of a human enzyme that can biodegrade carbon nanotubes. The researchers found that carbon nanotubes degraded with the human enzyme “myeloperoxidase” (hMPO) did not produce the lung inflammation that intact nanotubes have been shown to cause. Furthermore, neutrophils, the white blood cells that contain and emit hMPO to kill invading microorganisms, can be directed to attack carbon nanotubes specifically.

“The successful medical application of carbon nanotubes rely on their effective breakdown in the body, but carbon nanotubes also are notoriously durable,” said lead researcher Valerian Kagan, a professor and vice chair in the Department of Environmental and Occupational Health in Pitt‘s Graduate School of Public Health.“The ability of hMPO to biodegrade carbon nanotubes reveals that this breakdown is part of a natural inflamma- tory response. The next step is to develop methods for stimulating that inflammatory response and reproducing the biodegradation process inside a living organism.”

10-04 :: April 2010

After establishing the effectiveness of hMPO in degrading carbon nanotubes, the team developed a technique to prompt neutrophils to attack nano- tubes by capturing them and exposing them to the enzyme. They implanted a sample of nanotubes with antibodies known as immunoglobulin G (IgG), which made them specific neutrophil targets. After 12 hours, 100% of IgG nanotubes were degraded versus 30% of those without IgG. The researchers also tested the ability of macrophages, another white blood cell, to break down nanotubes, but after two days, only 50% of the tubes had degene- rated.

Valerian E. Kagan, Nagarjun V. Konduru, Weihong Feng, Brett L. Allen, Jennifer Conroy, Yuri Volkov, Irina I. Vlaso- va, Natalia A. Belikova, Naveena Yanamala, Alexander Ka- pralov, Yulia Y. Tyurina, Jingwen Shi, Elena R. Kisin, Ashley R. Murray, Jonathan Franks, Donna Stolz, Pingping Gou, Judith Klein-Seetharaman, Bengt Fadeel, Alexander Star & Anna A. Shvedova: Carbon nanotubes degraded by neu- trophil myeloperoxidase induce less pulmonary inflam- mation, In: Nature Nanotechnology AOP, April 04, 2010, DOI:10.1038/nnano.2010.44: http://dx.doi.org/10.1038/nnano.2010.44

New research findings suggest that an experimen-

tal ultrasensitive medical imaging technique that uses a pulsed laser and tiny metallic “nano-

cages” might enable both the early detection

and treatment of disease. The system works by

shining near-infrared laser pulses through the skin to detect hollow nanocages and solid nanoparti- cles – made of an alloy of gold and silver – that are injected into the bloodstream. Unlike previous approaches using tiny metallic nanorods and na- nospheres, the new technique does not cause heat