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Showing posts from June, 2012

Self-Assembling silver nanocubes

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Silver nanocubes Silver is one of the most impotant material for nanostructures because of its superior performance. Silver nanostructures have been synthesized with a range of different shapes, including spheres, discs, rods, wires, stars, prisms, right bipyramids, and cubes. Of these, single-crystal nanocubes are the most useful structure particularly for the production of gold nanocages as silver nanocubes serve as a sacrificial template. Synthesis Researchers of University of Washington have developed a polyol synthesis method which is a simple, robust and versatile one for producing silver nanocubes as monodispersed samples. Here silver atoms are formed by reducing AgNO3 precursor with ethylene glycol. Once the concentration of silver atoms has reached the supersaturation level, they will begin to nucleate and grow into silver nanostructures in the solution phase. the production rate of silver nanocubes can be improved  by adding a trace amount of sodium sulfide (Na2S) or sodium h

Protein nanomachines

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All creatures on earth survive by monitoring and transforming their environments with the help of small proteins made of thousands of atoms. But diseases such as Alzheimer's and Parkinson's are caused by errors in proteins assembly. Hence it becomes important to understanding how a protein goes from being one thing to becoming another to form a unique assembled structure. In this context scientists of University of Montreal have visualized how a protein goes from a linear chain to a unique assembled structure. Protein self-assembly Proteins are made of long linear chains of amino acids which self-assemble extremely rapidly into a working nanomachine. Lipid bilayers which are the basic structural elements of biological membranes help self-assembly and provide environment for proteins to operate. Both DNA and protein molecules possess a number of intrinsic properties such as the site-specific molecular recognition among interacting protein molecules and template-directed self ass

Controlled drug delivery by polymer layered nanorod

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Researchers at the University of Illinois at Urbana-Champaign in the US have created a set of gold nanorods with electrostatically trapped rhodamine 6G molecules on their surfaces. These molecules were used as model “drugs”. Successive layers of charged polymers – negatively charged poly (acrylic acid, sodium salt) and positively charged poly (allylamine hydrochloride)  were wrapped around the nanorods so that polymers alter the surface charge of the rods and help trap the rhodamine 6G molecules. It was found that the number of molecules  released from the rods can be related to the number of polymer layers wrapped around the rods and that the number of molecules released could be tuned 100-fold. This makes them promising as drug-delivery vehicles because of small size and easy functionalization of these structures. Gold nanorods can easily be made to absorb near-infrared laser irradiation of the electromagnetic spectrum to trigger drug release. The heat generated due to absorption of

Is nanotechnology data stolen?

Jianyu Huang working  at Sandia National Labs as a staff Scientist. He is working on materials physics, electron microscopy, battery, nanomechanics of nanotechnology.Since 2007 his publications have been quoted by more than 3800 times. He was arrested recently because he allegedly stole laboratory research and shared it with China.He is being accused of stealing research belonging to the U.S. that he claimed was his own original research. He allegedly shared with several Chinese universities and went online to share the data with the country’s state-run schools including Peking University and the Harbin Institute of Technology. But Sandia National Labs says that he did not have access to classified national security information. Huang was fired in April for removing a company-owned laptop from the facility. Sandia, a subsidiary of Lockheed Martin Corporation is known for its nuclear research, as well as the disposal of the U.S. nuclear weapons program’s hazardous waste and focusing on