Archive for the ‘nanoparticles’ tag
Nanostructures feel the chill
TEM image of cerium oxide nanorod formed in an ice channel
EMSL researchers and their collaborators, the University of Central Florida, Pacific Northwest National Laboratory, and Defence Academy of the United Kingdom, have tested a new way to build nanostructures that is ‘green’ and simple.
Researchers grew cerium oxide nanostructures inside the tiny voids that form in aqueous solutions on freezing. By controlling the solution freezing rate, nanoparticle concentration and storage temperature, the team’s ice mould method may be used to produce nanostructures with tailored shapes and sizes suitable for a variety of applications – from biology to electronics.
Read more on: Defence Academy of the United Kingdom, Electronics, EMSL, nanoparticles, nanostrctures, Pacific Northwest National Laboratory, University of Central FloridaNanoparticles in the home - more and smaller than previously detected
Extremely small nanoscale particles are released by common kitchen appliances in abundant amounts, greatly outnumbering the previously detected, larger-size nanoparticles emitted by these appliances, according to new findings* by researchers at the National Institute of Standards and Technology (NIST).
So-called “ultrafine particles” (UFP) range in size from 2 to 10 nanometers. They are emitted by motor vehicles and a variety of indoor sources and have attracted attention because of increasing evidence that they can cause respiratory and cardiovascular illnesses.
NIST researchers conducted a series of 150 experiments using gas and electric stoves and electric toaster ovens to determine their impacts on indoor levels of nano-sized particles. Previous studies have been limited to measuring particles with diameters greater than 10 nm, but new technology used in these experiments allowed researchers to measure down to 2 nm particles—approximately 10 times the size of a large atom.
This previously unexplored range of 2 to 10 nm contributed more than 90 percent of all the particles produced by the electric and gas stovetop burners/coils. The gas and electric ovens and the toaster oven produced most of their UFP in the 10 nm to 30 nm range.
The results of this test should affect future studies of human exposure to particulates and associated health effects, particularly since personal exposure to these indoor UFP sources can often exceed exposure to the outdoor UFP.
Researchers will continue to explore the production of UFP by indoor sources. Many common small appliances such as hair dryers, steam irons and electric power tools include heating elements or motors that may produce UFP. People often use these small appliances at close range for relatively long times, so exposure could be large even if the emissions are low.
The experiments were conducted in a three-bedroom test house at NIST that is equipped to measure ventilation rates, environmental conditions and contaminant concentrations.
Read more on: Electronics, nanoparticles, nanoscaleGold nanostar shape of the future
Rods, cones, cubes and spheres – move aside. Tiny gold stars, smaller than a billionth of a meter, may hold the promise for new approaches to medical diagnoses or testing for environmental contaminants.
While nanoparticles have been the rage across a wide spectrum of sciences, a new study by Duke University bioengineers indicates that of all the shapes studied to date, stars may shine above all the rest for certain applications.
The key is light, and how that light reflects off the particles. Compared to the other shapes, nanostars can dramatically enhance the reflected light, the Duke scientists found. This increases their potential usefulness as a tracer, label, or contrast agent.
Since the researchers also found that the size and shape of the nanostars affect the spectrum of reflected light, they believe that these tiny nanostars can also be “tuned” to identify particular molecules or chemicals.
“To our knowledge, this is the first report of the development and use of gold nanostars as labels for molecular detection and description of their controlled synthesis with different sizes and shapes” said Chris Khoury, lead author of a paper published on-line in the Journal of Physical Chemistry. Khoury is a graduate student in biomedical engineering working in the laboratory of senior researcher Tuan Vo-Dinh, R. Eugene and Susie E. Goodson Distinguished Professor of Biomedical Engineering and director of The Fitzpatrick Institute for Photonics at Duke.
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Non-invasive nanoparticle measurement
Technology that can determine the concentration of nanomaterials in living tissue has been licensed by The University of Texas at Austin to Houston-based nanoTox.
The technology was developed by James Tunnell, the Cockrell School of Engineering, which specialises in developing minimally invasive optical technologies for the detection, diagnosis and treatment if disease, in particular the application to cancer screening and therapeutics.
Read more on: Bio Tech, nanomaterial, nanoparticles, tissue, x-rayEngineers discover nanoparticles can break on through
In a finding that could speed the use of sensors or barcodes at the nanoscale, North Carolina State University engineers have shown that certain types of tiny organic particles, when heated to the proper temperature, bob to the surface of a layer of a thin polymer film and then can reversibly recede below the surface when heated a second time.
Read more on: Electronics, nanoparticlesNano-sized ‘trojan horse’ aids nutrition
Researchers from Monash University have designed a nano-sized ‘trojan horse’ particle to ensure healing antioxidants can be better absorbed by the human body.
Dr Ken Ng and Dr Ian Larson from the University’s Faculty of Pharmacy and Pharmaceutical Sciences have designed a nanoparticle, one thousandth the thickness of a human hair, that protects antioxidants from being destroyed in the gut and ensures a better chance of them being absorbed in the digestive tract.
Read more on: Bio Tech, nanoparticles, nanotechnologyNano-material is key to clean drinking water
Scientists at the University of South Australia, have discovered a simple way to remove bacteria and other contaminants from water using tiny particles of pure silica coated with an active nano-material.
The water treatment process is a new concept, not used anywhere else in the world, which has the potential to make a significant contribution to the health of nations worldwide.
A recent UNESCO report reveals that more than 6,000 people die every day from water-related diseases, and the availability of quality drinking water, especially in the developing world, is fast becoming a major socio-economic issue.
Read more on: Electronics, nanomaterial, nanoparticles, nanotechnology, waterNew disease-fighting nanoparticles look like miniature pastries
Ultra-miniature bialy-shaped particles, called nanobialys because they resemble tiny versions of the flat, onion-topped rolls popular in New York City, could soon be carrying medicinal compounds through patients’ bloodstreams to tumors or atherosclerotic plaques.
The nanobialys are an important addition to the stock of diagnostic and disease-fighting nanoparticles developed by researchers in the Consortium for Translational Research in Advanced Imaging and Nanomedicine (C-TRAIN) at Washington University School of Medicine in St. Louis.
C-TRAIN’s “smart” nanoparticles can deliver drugs and imaging agents directly to the site of tumors and plaques.
The nanobialys weren’t cooked up for their appealing shape — that’s a natural result of the manufacturing process. The particles answered a need for an alternative to the research group’s gadolinium-containing nanoparticles, which were created for their high visibility in magnetic resonance imaging (MRI) scans.
Read more on: Bio Tech, nanoparticlesSuper-resolution microscope reveals secrets of the nanoworld
A super-resolution X-ray microscope developed by a team of researchers from the Paul Scherrer Institut (PSI) and EPFL combines the high penetration power of x-rays with high spatial resolution, making it possible for the first time to shed light on the detailed interior composition of semiconductor devices and cellular structures.
It uses a Megapixel Pilatus detector which has excited the synchrotron community for its ability to count millions of single x-ray photons over a large area. This key feature makes it possible to record detailed diffraction patterns while the sample is raster-scanned through the focal spot of the beam. In contrast, conventional x-ray (or electron) scanning microscopes measure only the total transmitted intensity.
Read more on: Electronics, nanoelectronics, nanoparticlesMagnetic nanoparticles combat cancer
Scientists at Georgia Tech have developed a potential new treatment against cancer that attaches magnetic nanoparticles to cancer cells, allowing them to be captured and carried out of the body. The treatment has been tested in the laboratory and will now be looked at in survival studies.
They began by testing the therapy on mice. After giving the cancer cells in the mice a fluorescent green tag and staining the magnetic nanoparticles red, they were able to apply a magnet and move the green cancer cells to the abdominal region.
Read more on: Bio Tech, nanoparticles, nanotechnologyNanoparticles aid bone growth
In the first study of its kind, bioengineers and bioscientists at Rice University and Radboud University in Nijmegen, Netherlands, have shown they can grow denser bone tissue by sprinkling stick-like nanoparticles throughout the porous material used to pattern the bone.
It’s the latest breakthrough from the burgeoning field of tissue engineering. The new discipline combines the latest research in materials science and biomedical engineering to produce tissues that can be transplanted without risk of rejection.
Read more on: Bio Tech, nanoparticles