12-03 :: March/April 2012

nanotimes News in Brief

enough electricity to power 10,000 or more homes, according to some estimates.

http://www.jcvi.org/cms/about/bios/obretschger/

61

Engineers at Stanford University report the direct observation of plasmon resonances in individual metal particles measuring down to one nanome- ter in diameter. The research could lead to novel electronic or photonic devices based on excitation and detection of plasmons in these extremely small particles.

University of Central Florida Associate Professor J. Manuel Perez and Professor Saleh Naser and their research team have developed a novel tech- nique that may give doctors a faster and more sensitive tool to detect pathogens associated with inflammatory bowel disease, including Crohn’s disease. The new nanoparticle-based technique also may be used for detection of other microbes that have challenged scientists for centuries becau- se they hide deep in human tissue and are able to reprogram cells to successfully evade the immune system.

The team created hybridizing magnetic relaxation nanosensors (hMRS) that can fish out and detect minuscule amounts of DNA from pathogens hiding within a patient’s cells. The hair-thin hMRS are composed of a polymer-coated iron oxide nano- particle and are chemically modified to specifically bind to a DNA marker that is unique to a particular pathogen.

Charalambos Kaittanis, Hamza Boukhriss, Santimukul Santra, Saleh A. Naser, J. Manuel Perez: Rapid and Sen- sitive Detection of an Intracellular Pathogen in Human Peripheral Leukocytes with Hybridizing Magnetic Rela- xation Nanosensors, In: PLoS ONE 7(4), April 9, 2012, e35326, DOI:10.1371/journal.pone.0035326: http://dx.doi.org/10.1371/journal.pone.0035326

“Plasmon resonances at these scales are poorly understood,” said Jonathan Scholl, first author of the paper. “So, this class of quantum-sized metal nanoparticles has gone largely under-utilized in engineering. Exploring their size-dependent nature could open up some interesting applications at the nanoscale.”

“Alternatively, there could be opportunities in cata- lysis, quantum optics, and bio-imaging and thera- peutics,” added researcher Jennifer A. Dionne.

A series of electron micrographs of silver nanospheres of between two and ten nanometers in diameter. Individual atoms are visible within the particles. © Jonathan Scholl/ Stanford Engineering

Jonathan A. Scholl, Ai Leen Koh, Jennifer A. Dionne: Quantum plasmon resonances of individual metallic na- noparticles, In: Nature, Vol. 483, Issue 7390, March 21, 2012, Pages 421-427, DOI:10.1038/nature10904: http://dx.doi.org/10.1038/nature10904