Miriam Wilsonwith molecules for moving parts, this nanorobot links together amino acids (colored balls) by attaching them to a moving ring (blue.
In its present incarnation, the nanomachine requires the axle to be preloaded with amino acids in the correct sequence.
#Electron beams set nanostructures aglow Put a piece of quartz under an electron microscope and it will shine an icy blue.
turning the glow into a precise probe of a material s nanoscale structure. The researchers expect the technology to reach the market early this year,
giving materials scientists a new tool for investigating the behaviour of light in the interiors of the complex nanostructures used in lasers, light-based circuits and solar cells."
An electron beam can in principle achieve a resolution of less than one nanometre, compared with hundreds of nanometres for a beam of light.
But maps made by scattered or reflected electrons are not typically sensitive to the way light behaves in the sample.
it promises the same nanometre scale resolution that those systems can achieve.""This has opened the door to understanding how light couples to matter in a more fundamental way,
along with collaborators in the United states and Spain, has used the technique to tease out how certain nanostructures interact with light.
The team has mapped also the distribution of light in the silicon nanodiscs that are used as a coating on solar cells to improve efficiency,
#Stealth nanoparticles sneak past immune system s defences Small man-made peptides can help to sneak drug-bearing nanobeads past the ever-vigilant immune system,
Although scientists are developing nanoparticles that help to deliver drugs to the right place, all therapeutic molecules face a deadly foe#the immune system.
Researchers at the University of Pennsylvania in Philadelphia have now found a way to stop macrophages from destroying drug-bearing nanoparticles.
They then stuck the peptide to commercially available polystyrene nanobeads. The beads also carried a dye
fluorescent nanobeads accumulated in the tumours. Nanoparticles tend to accumulate in tumours because of the tumour s haphazard structure and leaky blood vessels.
The nanoparticles spill through these blood vessels and get stuck in the tumour. Buoyed by the evidence that the peptide-carrying nanobeads were circulating in the blood
Discher and his team also tagged their nanobeads with the anticancer drug paclitaxel. They saw that their peptide-carrying system shrank tumours just as well as the standard paclitaxel carrier, Cremophor,
but without that carrier's toxic side effects. Neil Barclay of the University of Oxford, UK, was part of the team that worked out the CD47 structure that inspired Discher s work2."
"It s neat, he says of Discher s research.""It s a new way of trying to get the immune system to prevent phagocytosis of drugs or particles.
Discher hopes that the system can be improved with custom-made nanobeads, rather than being limited to the off-the-shelf ones he and his team used."
Although the difference was a mere 0. 3 nanometres, about the width of three helium atoms,
If the semiconductor is small enough#a nanoparticle, for example#a single electron can switch the transistor on,
A handful work at room temperature (by using carbon nanotubes to detect electrons for example2), but they cannot operate in water#a serious obstacle to using such devices in living organisms.
They strung together thousands of gold nanoparticles, each 10 nanometres across, into long necklaces. These can form a tangled network that connects two electrodes some 30 micrometres apart.
Roughly 5%of the gold nanoparticles have defects that prevent current from flowing from one electrode to the other.
But if an electron settles on a defective nanoparticle it makes it slightly easier for current to flow,
says Ulrich Simon, a nanoscience researcher at the RWTH Aachen University in Germany. Now, Saraf s team has shown that the nano-necklace device works in water
#Researchers Enlarge Brain Samples Making Them Easier to Image New technique enables nanoscale-resolution microscopy of large biological specimens.
The latest generation of so-called uper-resolutionmicroscopes can see inside cells with resolution better than 250 nanometers.
the researchers say. nstead of acquiring a new microscope to take images with nanoscale resolution,
if you are using blue-green light with a wavelength of 500 nanometers, you can see anything smaller than 250 nanometers. nfortunately,
in biology that right where things get interesting, says Boyden, who is a member of MIT Media Lab and Mcgovern Institute for Brain Research.
and other cellular activities are organized all at the nanoscale. Scientists have come up with some eally clever tricksto overcome this limitation,
you have to look at a large piece of tissue with nanoscale precision, he says. To achieve this, the MIT team focused its attention on the sample rather than the microscope.
but usually limited to a resolution of hundreds of nanometers. With their enlarged samples, the researchers achieved resolution down to 70 nanometers. he expansion microscopy process should be compatible with many existing microscope designs and systems already in laboratories,
Chen adds. Large tissue samples Using this technique, the MIT team was able to image a section of brain tissue 500 by 200 by 100 microns with a standard confocal microscope.
MIT researchers led by Ed Boyden have invented a new way to visualize the nanoscale structure of the brain and other tissues.
but also to see where all the nanoscale components are. While Boyden team is focused on the brain,
chemistry professor at Harvard university and lead author on the new paper published in the journal Nature Nanotechnology. ou can promote a positive interaction
Bao via e-mail. am impressed that they were able to inject even the nanowire transistors with very high yield.""
#'Wi-fi'Nanoparticles Send Signals from the Brain The problem with talking to our own brains,
A medical research team at Florida International University in Miami injected 20 billion nanoparticles into the brains of mice
the electric field can directly couple to the electric circuitry of the neural network. he nanoparticles could be used to deliver drugs to specific parts of the brain.
the nanoparticles could generate measurable magnetic fields in response to the brain electrical fields. Toggle the system back
which was a scant 25 nanometers deep. The holes had different diameters ranging from 45 to 75 nanometers
and corresponded to the desired absorption of light at various wavelengths. When light was shined onto the structure
Within each of the tiny particles is an elaborate nanopore structure think of it as a series of microscopic holes within a thin membrane,
Manufacturing these structures is part of an elaborate process that involves breaking down the nanopore structures into niform-sized particlesthat are fabricated ompletely
Gold nanoparticles Could Detect Disease: Discovery Newsprevious studies have shown that diseases such as lung and esophageal cancer,
New research suggests that a certain type of artificial diamond can be used as a nanoscale temperature probe with unmatched precision over time
but Jaque suspects theyl be most useful for observing the nanoscopic world, in particular the minute temperature fluctuations in living cells.
#Interplanetary comms get easier with a nanotech boost E t. MANAGED to phone home. But what about our own future Mars colonies or space probes millions of kilometres away?
Now a nanoscale light detector could make such deep-space missives easier to read. So says Richard Mirin at the US National Institute of Standards
Mirin made a nanowire detector that operates at-270 C. This boosted the number of photons it received each second by two orders of magnitude compared with regular detectors.
it will probably be thanks to MIT spinout QD Vision, a pioneer of quantum dot television displays.
Quantum dots are light-emitting semiconductor nanocrystals that can be tuned by changing their size, nanometer by nanometer to emit all colors across the visible spectrum.
By tuning these dots to red and green, and using a blue backlight to energize them,
Last June, Sony used QD Vision product, called Color IQ, in millions of its Bravia riluminostelevisions, marking the first-ever commercial quantum dot display.
filled with quantum dots tuned to red and green, that implemented during the synthesis process. Manufacturers use a blue LED in the backlight,
on implementing quantum dots into electronic devices. In a study funded by MIT Deshpande Center for Technological Innovation, Coe-Sullivan, QD Vision cofounder Jonathan Steckel Phd 6,
and others developed a pioneering technique for producing quantum dot LEDS (QLEDS). To do so, they sandwiched a layer of quantum dots, a few nanometers thick, between two organic thin films.
When electrically charged, the dots illuminated a light bulb 25 times more efficiently than traditional devices.
became a landmark in the quantum dot-devices field. oon venture capitalists were calling Vladimir, asking if we spin a company out,
quantum dot displays. aking a transition like that from lighting to displays tests the nerves of folks involved, from top to bottom,
and last year became the first to market with a quantum dot display. Today, QD Vision remains one of only two quantum dot display companies that have seen their products go to market.
Now, with a sharp rise in commercial use, quantum dot technologies are positioned to penetrate the display industry
Coe-Sullivan says. Along with Color IQ-powered LCD TVS, Amazon released a quantum dot Kindle last year,
and Asus has a quantum dot notebook. nd there nothing in between that quantum dots can address,
he says. In the future, Coe-Sullivan adds, QD Vision may even go back and tackle its first challenge:
and value proposition for quantum dot lighting. n
#Hewlett Foundation funds new MIT initiative on cybersecurity policy MIT has received $15 million in funding from the William
#Two sensors in one MIT chemists have developed new nanoparticles that can simultaneously perform magnetic resonance imaging (MRI) and fluorescent imaging in living animals.
The researchers found that their imaging particles accumulated in the liver as nanoparticles usually do.
They have created also nanoparticles carrying the fluorescent agent plus up to three different drugs. This allows them to track
whether the nanoparticles are delivered to their targeted locations. That s the advantage of our platform we can mix
Steven Bottle a professor of nanotechnology and molecular science at Queensland University of Technology says the most impressive element of the study is the combination of two powerful imaging techniques into one nanomaterial.
From walls to nanoscale chips This fall Spielberg jumped to the other end of the 3-D printing spectrum, moving from walls to nanoscale fluidic chips.
He is now working in the lab of A. John Hart, the Mitsui Career development Associate professor of Mechanical engineering,
#Nanoparticles get a magnetic handle A long-sought goal of creating particles that can emit a colorful fluorescent glow in a biological environment
The new technology could make it possible to track the position of the nanoparticles as they move within the body or inside a cell.
At the same time the nanoparticles could be manipulated precisely by applying a magnetic field to pull them along. And finally the particles could have a coating of a bioreactive substance that could seek out
It s been a dream of mine for many years to have a nanomaterial that incorporates both fluorescence
All of these goals are achieved by the new nanoparticles which can be identified with great precision by the wavelength of their fluorescent emissions.
and postdoc Ou Chen the nanoparticles crystallize such that they self-assemble in exactly the way that leads to the most useful outcome:
That puts the fluorescent molecules in the most visible location for allowing the nanoparticles to be tracked optically through a microscope.
because the starting material fluorescent nanoparticles that Bawendi and his group have been perfecting for years are themselves perfectly uniform in size.
The next step for the team is to test the new nanoparticles in a variety of biological settings.
Christopher Murray a professor of chemistry and materials science and engineering at the University of Pennsylvania who was connected not with this research says This work exemplifies the power of using nanocrystals as building blocks for multiscale and multifunctional structures.
The work was supported by the National institutes of health the Army Research Office through MIT s Institute for Soldier Nanotechnologies and the Department of energy y
#Fast cheap nanomanufacturing Luis Fernando Velsquez-Garc a s group at MIT s Microsystems Technology Laboratories (MTL) develops dense arrays of microscopic cones that harness
depositing or etching features onto nanoscale mechanical devices; spinning out nanofibers for use in water filters body armor and smart textiles;
or propulsion systems for fist-sized nanosatellites. In the latest issue of the IEEE Journal of Microelectromechanical systems Velsquez-Garc a his graduate students Eric Heubel and Philip Ponce de Leon and Frances Hill a postdoc in his group describe a new prototype
array that generates 10 times the ion current per emitter that previous arrays did. Ion current is a measure of the charge carried by moving ions
But in the new work they instead used carbon nanotubes atom-thick sheets of carbon rolled into cylinders grown on the slopes of the emitters like trees on a mountainside.
and height of the nanotubes the researchers were able to achieve a fluid flow that enabled an operating ion current at very near the theoretical limit.
That s crucial for nanofabrication applications in which the depth of an etch or the height of deposits must be consistent across an entire chip.
To control the nanotubes growth the researchers first cover the emitter array with an ultrathin catalyst film
The nanotubes grow up under the catalyst particles which sit atop them until the catalyst degrades.
The emitters like most nanoscale silicon devices were produced through photolithography a process in which patterns are transferred optically to layers of materials deposited on silicon wafers;
Nanoprintingvelsquez-Garca believes that using arrays of emitters to produce nanodevices could have several advantages over photolithography the technique that produces the arrays themselves.
and don t require a vacuum chamber the arrays could deposit materials that can t withstand the extreme conditions of many micro-and nanomanufacturing processes.
In my opinion the best nanosystems are going to be done by 3-D printing because it would bypass the problems of standard microfabrication Velsquez-Garca says.
Using their nanotube forest they re able to get the devices to operate in pure ion mode
For this study Yanik s team developed a new technology to inject RNA carried by nanoparticles called lipidoids previously designed by Daniel Anderson an associate professor of chemical engineering member of the Koch Institute for Integrative Cancer Research and Institute
#The ability to identify useful drug delivery nanoparticles using this miniaturized system holds great potential for accelerating our discovery process Anderson says.
and tumor-suppressor gene p53 is deleted researchers injected mice with RNA-carrying nanoparticles. This mouse model reflects many of the hallmarks of human lung cancer
The nanoparticles are made of a small polymer lipid conjugate; unlike liver-targeting nanoparticles these preferentially target the lung
and are tolerated well in the body. They were developed in the laboratories of co-senior author Daniel G. Anderson the Samuel A. Goldblith Associate professor of Chemical engineering an affiliate of MIT's Institute of Medical Engineering and Science;
In this study researchers tested the nanoparticle-delivery system with different payloads of therapeutic RNA. They found that delivery of mir-34a a p53-regulated mirna slowed tumor growth as did delivery of sikras a KRAS-targeting sirna.
Next researchers treated mice with both mir-34a and sikras in the same nanoparticle. Instead of just slowing tumor growth this combination therapy caused tumors to regress
treatment#with nanoparticles carrying both mir-34a and sikras; and treatment#with both cisplatin and the nanoparticles.
They found that the nanoparticle treatment extended life just as well as the cisplatin treatment and furthermore that the combination therapy of the nanoparticles and cisplatin together extended life by about an additional 25 percent.
Potential for personalized cancer treatmentsthis early example of RNA combination therapy demonstrates the potential of developing personalized cancer treatments.
We took the best mouse model for lung cancer we could find we found the best nanoparticle we could use
However nanoparticles and other delivery methods now being developed for DNA and RNA could prove more effective in targeting other organs Sharp says.
In the near term the material could also be embedded in lab-on-a-chip devices to magnetically direct the flow of cells and other biological material through a diagnostic chip s microchannels.
Tiny ferromagnetic particles approximately 10 nanometers in diameter in the ferrofluid could allow precision control
#Light pulses control graphene s electrical behavior Graphene, an ultrathin form of carbon with exceptional electrical optical and mechanical properties, has become a focus of research on a variety of potential uses.
The researchers found that by controlling the concentration of electrons in a graphene sheet they could change the way the material responds to a short but intense light pulse.
If the graphene sheet starts out with low electron concentration the pulse increases the material s electrical conductivity.
But if the graphene starts out with high electron concentration the pulse decreases its conductivity the same way that a metal usually behaves.
Therefore by modulating graphene's electron concentration the researchers found that they could effectively alter graphene's photoconductive properties from semiconductorlike to metallike.
The finding also explains the photoresponse of graphene reported previously by different research groups which studied graphene samples with differing concentration of electrons.
We were able to tune the number of electrons in graphene and get either response,
To perform this study the team deposited graphene on top of an insulating layer with a thin metallic film beneath it;
by applying a voltage between graphene and the bottom electrode the electron concentration of graphene could be tuned.
The researchers then illuminated graphene with a strong light pulse and measured the change of electrical conduction by assessing the transmission of a second low-frequency light pulse.
In this case the laser performs dual functions. We use two different light pulses: one to modify the material and one to measure the electrical conduction.
This all-optical method avoids the need for adding extra electrical contacts to the graphene. Gedik the Lawrence C. and Sarah W. Biedenharn Associate professor of Physics says the measurement method that Frenzel implemented is a cool technique.
and reveal graphene's electrical response in only a trillionth of a second. In a surprising finding the team discovered that part of the conductivity reduction at high electron concentration stems from a unique characteristic of graphene:
its electrons travel at a constant speed similar to photons which causes the conductivity to decrease when the electron temperature increases under the illumination of the laser pulse.
Our experiment reveals that the cause of photoconductivity in graphene is very different from that in a normal metal or semiconductors,
therefore require increasing absorption efficiency such as by using multiple layers of graphene, Gedik says. Isabella Gierz a professor at the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg Germany who was involved not in this research says:"
The research team also included Jing Kong the ITT Career development Associate professor of Electrical engineering at MIT who provided the graphene samples used for the experiments;
Recently, scientists have explored ways to improve the efficiency of solar-thermal harvesting by developing new solar receivers and by working with nanofluids.
The latter approach involves mixing water with nanoparticles that heat up quickly when exposed to sunlight, vaporizing the surrounding water molecules as steam.
The difficulty significantly increases for nanoemulsions where the drop sizes are below a micron. To break down those emulsions crews use de-emulsifiers
The membranes combine a very thin layer of nanopores with a thicker layer of micropores to limit the passage of unwanted material
in order to block them Varanasi says which in the case of nanoemulsions leads to very small pores
an ingenious process that makes large holes on one side that penetrate most of the way through the material providing little resistance to flow as well as nanoscale holes on the other surface in contact with the emulsion to be separated.
The thin layer with nanoscale pores allows for separation and the thick layer with large pores provides mechanical support.
Solomon performed experiments showing the effectiveness of the membranes in separating nanoemulsions while maintaining integrity at high pressure.
Anish Tuteja an assistant professor of materials science and engineering at the University of Michigan who was involved not in this research calls it a very interesting and innovative approach to fabricating membranes that can separate out nanoemulsions.
Oil-water nanoemulsions are ubiquitous in a number of industries and these membranes could enable rapid separation of those emulsions with high purity and efficiency.
That combination of order and disorder contributes to eumelanin broadband absorption, the team found. t a naturally existing nanocomposite,
hat has very critical macroscopic properties as a result of the nanostructure. While eumelanin molecules all share a basic chemistry,
in part because it is a natural destination for nanoparticles. But now, in a study appearing in the May 11 issue of Nature Nanotechnology,
an MIT-led team reports achieving the most potent RNAI gene silencing to date in nonliver tissues.
Using nanoparticles designed and screened for endothelial delivery of short strands of RNA called sirna,
Anderson and Langer have developed previously nanoparticles, now in clinical development, that can deliver sirna to liver cells called hepatocytes by coating the nucleic acids in fatty materials called lipidoids.
because they resemble the fatty droplets that circulate in the blood after a high-fat meal is consumed. he liver is a natural destination for nanoparticles,
if you inject nanoparticles into the blood, they are likely to end up there. Scientists have had some success delivering RNA to nonliver organs
they did not enter liver hepatocytes. hat interesting is that by changing the chemistry of the nanoparticle you can affect delivery to different parts of the body,
the researchers used the nanoparticles to block two genes that have been implicated in lung cancer VEGF receptor 1 and Dll4,
which relies on a nanoparticle that carries two drugs and releases them at different times,
and Paula Hammond, the David H. Koch Professor in Engineering, describe the findings in the May 8 online edition of Science Signaling. think it a harbinger of what nanomedicine can do for us in the future,
who is a member of MIT Koch Institute for Integrative Cancer Research. ee moving from the simplest model of the nanoparticle just getting the drug in there
and targeting it to having smart nanoparticles that deliver drug combinations in the way that you need to really attack the tumor.
a chemical engineer who has designed previously several types of nanoparticles that can carry two drugs at once.
Furthermore, packaging the two drugs in liposome nanoparticles made them much more effective than the traditional forms of the drugs,
At the same time, Hammond lab is working on more complex nanoparticles that would allow for more precise loading of the drugs
and fine-tuning of their staggered release. ith a nanoparticle delivery platform that allows us to control the relative rates of release and the relative amounts of loading,
The work was funded by the National institutes of health, the Center for Cancer Nanotechnology Excellence, the Koch Institute Frontier Research Program supported by the Kathy and Curt Marble Fund for Cancer Research,
and work at the Center for Functional Nanomaterials at Brookhaven National Laboratory was supported by the U s. Department of energy t
The research was funded by the National Cancer Institute Centers of Cancer Nanotechnology Excellence and the U s army Research Office e
The particles determine how energy moves at the nanoscale. The efficiency of devices such as photovoltaics and LEDS depends on how well excitons move within the material he adds.
This allows us to see new things Deotare says making it possible to demonstrate that the nanoscale structure of a material determines how quickly excitons get trapped as they move through it.
Grossman team tried attaching the molecules to carbon nanotubes (CNTS), but t incredibly hard to get these molecules packed onto a CNT in that kind of close packing,
Kucharski says. But then they found a big surprise: Even though the best they could achieve was a packing density less than half of
called azobenzene, protrude from the sides of the CNTS like the teeth of a comb.
they were interleaved with azobenzene molecules attached to adjacent CNTS. The net result: The molecules were actually much closer to each other than expected.
The interactions between azobenzene molecules on neighboring CNTS make the material work, Kucharski says. While previous modeling showed that the packing of azobenzenes on the same CNT would provide only a 30 percent increase in energy storage,
the experiments observed a 200 percent increase. New simulations confirmed that the effects of the packing between neighboring CNTS,
as opposed to on a single CNT, explain the significantly larger enhancements. This realization, Grossman says,
opens up a wide range of possible materials for optimizing heat storage. Instead of searching for specific photoswitching molecules
The adoption of carbon nanotubes to increase materialsenergy storage density is lever, says Yosuke Kanai, an assistant professor of chemistry at the University of North carolina who was involved not in this work.
contain colored stripes of nanocrystals that glow brightly when lit up with near-infrared light. These particles can easily be manufactured
and include several stripes of different colored nanocrystals, known as are earth upconverting nanocrystals. These crystals are doped with elements such as ytterbium, gadolinium, erbium,
and thulium, which emit visible colors when exposed to near-infrared light. By altering the ratios of these elements,
In this case, each polymer stream contains nanocrystals that emit different colors, allowing the researchers to form striped particles.
So far, the researchers have created nanocrystals in nine different colors, but it should be possible to create many more,
and youl never get the same combination. he use of these upconverting nanocrystals is quite clever and highly enabling,
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