Articles from May 2013



Fast Virus Test At The Medical Office

Two independent teams (University of Caliofornia Los AngelesUCLA– and University of California Santa Cruz UCSC-) have developed new optics-based methods for determining the exact viral load of a sample by counting individual virus particles. These new methods are faster and cheaper than standard tests and they offer the potential to conduct the measurements in a medical office or hospital instead of a laboratory. The teams will present their latest results at the Conference on Lasers and Electro-Optics (CLEO: 2013), to be held June 9-14, in San Jose, Calif.

optofluidic chip
Photograph of 1cm x 1cm optofluidic chip for direct detection of viral nucleic acids

Because viruses are very small–less than 100 billionths of a meter–compared to the wavelength of light, conventional light microscopy has difficulty producing an image due to weak scattering of sub-wavelength particles,” says Aydogan Ozcan of UCLA. When lighted, the team’s new nanolens-nanoparticle assembly projects a hologram that can be recorded using a CMOS imager chip (a type of semiconductor-based light detector) and digitally reconstructed to form an optical image of the particle. “The resulting image improves the field-of-view of a conventional optical microscope by two orders of magnitude,” says Ozcan.
Source: http://www.osa.org/

Grapefruits, Secret Weapon To Deliver Drugs

University of Louisville UofL -researchers have uncovered how to create nanoparticles using natural lipids derived from grapefruit, and have discovered how to use them as drug delivery vehicles. Grapefruits have long been known for their health benefits, and the subtropical fruit may revolutionize how medical therapies like anti-cancer drugs are delivered to specific tumor cells.The researchers demonstrated that GNVs can transport various therapeutic agents, including anti-cancer drugs, DNA/RNA and proteins such as antibodies. Treatment of animals with GNVs seemed to cause less adverse effects than treatment with drugs encapsulated in synthetic lipids.

grapefruit

Our GNVs can be modified to target specific cells – we can use them like missiles to carry a variety of therapeutic agents for the purpose of destroying diseased cells,” said Huang-Ge Zhang, from The School of Medecine – University of Louisville. “Furthermore, we can do this at an affordable price.”

The therapeutic potential of grapefruit derived nanoparticles was further validated through a Phase 1 clinical trial for treatment of colon cancer patients. So far, researchers have observed no toxicity in the patients who orally took the anti-inflammatory agent curcumin encapsulated in grapefruit nanoparticles.

UofL scientists Huang-Ge Zhang, D.V.M., Ph.D., Qilong Wang, Ph.D., and their team, published their findings in Nature Communications.
Source: http://louisville.edu/

Exploring New Ways to Power Mobile Phones

Physicist Florian Nitze, from Umeå University – Sweden -, has developed new catalysts to improve the capacity of fuel cells, able to power mobile phones or laptops, using environmental friendly formic acid. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run. The technology is already commercially available but formic acid fuel cells still suffer from low power and lifetime.
The effect of a catalyst is to reduce the energy loss and to increase the rate of the chemical reactions, which leads to a higher efficiency in the fuel cell.
In his thesis, Florian Nitze has developed new catalysts based on a combination of material science and nanotechnology – engineering close to the atom level.

fiber-med-nanopartiklar_webb

“Especially catalysts of palladium-nanoparticles attached to a unique helical formed carbon nanofibre proved to have a long lifetime and a very high potential to be used in formic acid fuel cells. The helical formed carbon nanofibre has a high electrical conductivity and a surface that is very easy to decorate with nanoparticles, “ says Florian Nitze.
Formic acid can be produced from renewable sources, i.e. wood, and is therefore a highly environmentally friendly alternative.
One of the major advantages over Li-ion batteries, which are dominating the battery market, is that the charging only takes seconds by simple refueling with formic acid,” says Florian Nitze.
Source: http://www.teknat.umu.se/

Nano Hazards: 4 Different Exposures And 7 Risks

According to a highly experienced specialist of nanotechnogies, Willy Verbrugghe, 85% of the products issued from the nano world are safe, 5 % potentially dangerous, and 10 % are still under scrutinity. Verbrugghe, from the US company Nanotox (Austin – Texas) has presented last week In Paris a memorandum related to various potential hazards human beings have to face when involved with nanotechnologies. Major problem to address for the nano industry is to define precisely what is nano and what is NOT nano in order, for instance, to establish safety rules, to sell devices inside a legal frame, to go on researches on an international basis, etc…
Nano particles change properties and interaction with size, and with the milieu in which they travel. This is called the CORONA Effect. So it is critical to characterize the particle: material, form, size, distribution, composition, surface, shape, porosity, dose, coating, purity,…

silver nanoparticles
As well it is important to define the role, function, partnering, environment, residence time, life cycle of the particle. Sometimes a case by case assessment of the risk is the only way to proceed when there are too many unknown.

Full impact of nano particles has to be determined with relevant coronas and absorption/retention/desorbtion mechanisms in the human body and the environment. Why? Because nano particles in different biologic fluids (thus different coronas) behave diffferently depending on the exposure and route of entry.

We can state 4 different types of exposure:
Inhalation, Skin contact, Oral and Invasive.

You will find potential hazards in 7 categories: Devices, Occupational health, Environment, Textile, Materials, Food and Cosmetics.
Willy Verbrugghe underscores that it is in the cosmetic industry that you may worry about potentially dangerous effects using products like lipsticks, anti-aging cream or sunscreen cream.
Willy Verbrugghe

The company NANOTOX intervenes in all the aspects of the nanoworld and provides complete worldwide nano safety suite of services:
 Toxicology evaluation, human and environment
 Risk assessments, dossiers, defense, regulatory
NanoTox Services
 EH&S Program Accreditation and audits
 BIO Nano Consulting, Exchange, Data Bases
Facilities EPC:
 Nano Design, Engineering, Operations
 EH&S Implementation
Future developments in Advanced Throughput, Testing
Protocols, Industry Standards and regulations, …

Source: http://nanotox.com/

How To Grow New Brains

A new tool being developed by the University of Texas Arlington (UT Arlington) assistant professor Samarendra Mohanty could help scientists map and track the interactions between neurons inside different areas of the brain. More the development of a fiber-optic, two-photon, optogenetic stimulator and its use on human cells in a laboratory could lead to grew new brains. The tiny tool builds on Mohanty’s previous discovery that near-infrared light can be used to stimulate a light-sensitive protein introduced into living cells and neurons in the brain. This new method could show how different parts of the brain react when a linked area is stimulated.

artificialBrain

Scientists have spent a lot of time looking at the physical connections between different regions of the brain. But that information is not sufficient unless we examine how those connections function,” Mohanty said. “That’s where two-photon optogenetics comes into play. This is a tool not only to control the neuronal activity but to understand how the brain works.

Source: https://www.uta.edu/

One Step Closer To The Human Cloning

Researchers at Oregon Health & Science UniversityOHSU – have made a significant breakthrough in efforts to develop human stem cell therapies that may be used to combat numerous devastating diseases. For the first time, scientists have successfully derived embryonic stem cells by reprogramming of genetic material from skin cells while studying rhesus macaque monkeys. The breakthrough follows several previously unsuccessful attempts by the OHSU-based team and other scientific teams worldwide.
HUMAN CLONES
Many scientists believe that embryonic stem cells hold great promise for treating a variety of diseases including Parkinson’s disease, multiple sclerosis, cardiac disease and spinal cord injuries,” explained Shoukhrat Mitalipov, Ph.D., director of the OHSU-based research team. “Using our advanced methods, it is conceivable that years from now, patients could receive therapeutic embryonic stem cells developed from their very own cells meaning that there would be no concerns about transplant rejection. Another noteworthy aspect of this research is that it does not involve the use of fertilized embryos, a topic which has been the source of a significant ethical debate in this country.

Neverthless “it’s a matter of time before they produce a cloned monkey,” said Jose Cibelli, a cloning expert at Michigan State University, who wasn’t involved in the study. It also means, he added, “that they are one step closer to where the efficiency is high enough that someone is willing to try” to clone a person.

The results of the work were released online by the scientific journal Nature.
Source: http://www.ohsu.edu

Semiconductor At the Atomic Scale For NanoComputers

Researchers at North Carolina State University have developed a new technique for creating high-quality semiconductor thin films at the atomic scale – meaning the films are only one atom thick. The technique can be used to create these thin films on a large scale, sufficient to coat wafers that are two inches wide, or larger.

one atom thick
This could be used to scale current semiconductor technologies down to the atomic scale – lasers, light-emitting diodes (LEDs), computer chips, anything,” says Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and senior author of a paper on the work. “People have been talking about this concept for a long time, but it wasn’t possible. With this discovery, I think it’s possible.”
The key to our success is the development of a new growth mechanism, a self-limiting growth,” Cao says. The researchers can precisely control the thickness of the MoS2 layer by controlling the partial pressure and vapor pressure in the furnace. Partial pressure is the tendency of atoms or molecules suspended in the air to condense into a solid and settle onto the substrate. Vapor pressure is the tendency of solid atoms or molecules on the substrate to vaporize and rise into the air.

Source: http://news.ncsu.edu/

Low-cost, Foldable Electronics

Imagine a bendable tablet computer or an electronic newspaper that could fold to fit in a pocket. The technology for these devices may not be so far off. Northwestern University researchers have recently developed a graphene-based ink that is highly conductive and tolerant to bending, and they have used it to inkjet-print graphene patterns that could be used for extremely detailed, conductive electrodes.
The resulting patterns are 250 times more conductive than previous attempts to print graphene-based electronic patterns and could be a step toward low-cost, foldable electronics.

bendable tablet

Graphene has a unique combination of properties that is ideal for next-generation electronics, including high electrical conductivity, mechanical flexibility, and chemical stability,” said Mark Hersam, professor of materials science and engineering at Northwestern’s McCormick School of Engineering and Applied Science. “By formulating an inkjet-printable ink based on graphene, we now have an inexpensive and scalable path for exploiting these properties in real-world technologies.”
A paper describing the research, has been published in the Journal of Physical Chemistry Letters.
Source: http://www.mccormick.northwestern.edu/

How To Grow Bone

Researchers from Brigham and Women’s Hospital (BWH) are the first to report that synthetic silicate nanoplatelets (also known as layered clay) can induce stem cells to become bone cells without the need of additional bone-inducing factors. Synthetic silicates are made up of simple or complex salts of silicic acids, and have been used extensively for various commercial and industrial applications, such as food additives, glass and ceramic filler materials, and anti-caking agents.
Silicate Nanoplatelets

With an aging population in the US, injuries and degenerative conditions are subsequently on the rise,” said Ali Khademhosseini, PhD, BWH Division of Biomedical Engineering, senior study author. “As a result, there is an increased demand for therapies that can repair damaged tissues. In particular, there is a great need for new materials that can direct stem cell differentiation and facilitate functional tissue formation. Silicate nanoplatelets have the potential to address this need in medicine and biotechnology.”
The study has been published online May 13, 2013 in Advanced Materials.

Source: http://www.brighamandwomens.org/

How To Create Artificial Nano Flowers

With the hand of nature trained on a beaker of chemical fluid, the most delicate flower structures have been formed in a Harvard laboratory—and not at the scale of inches, but microns. These minuscule sculptures, curved and delicate, don’t resemble the cubic or jagged forms normally associated with crystals, though that’s what they are. Rather, fields of carnations and marigolds seem to bloom from the surface of a submerged glass slide, assembling themselves a molecule at a time.By simply manipulating chemical gradients in a beaker of fluid, Wim L. Noorduin, a postdoctoral fellow at the Harvard School of Engineering and Applied Sciences (SEAS) and lead author of a paper appearing on the cover of Science, has found that he can control the growth behavior of these crystals to create precisely tailored structures.
nano tulip
For at least 200 years, people have been intrigued by how complex shapes could have evolved in nature. This work helps to demonstrate what’s possible just through environmental, chemical changes,” says Noorduin.
Source: https://www.seas.harvard.edu/

Artificial Forest for Solar Water-Splitting

In the wake of the sobering news that atmospheric carbon dioxide is now at its highest level in at least three million years, an important advance in the race to develop carbon-neutral renewable energy sources has been achieved. Scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have reported the first fully integrated nanosystem for artificial photosynthesis. While “artificial leaf” is the popular term for such a system, the key to this success was an “artificial forest.”

nanowires for artificial forest
Schematic shows TiO2 nanowires (blue) grown on the upper half of a Si nanowire (gray) and the two absorbing different regions of the solar spectrum

Similar to the chloroplasts in green plants that carry out photosynthesis, our artificial photosynthetic system is composed of two semiconductor light absorbers, an interfacial layer for charge transport, and spatially separated co-catalysts,” says Peidong Yang, a chemist with Berkeley Lab’s Materials Sciences Division, who led this research. “To facilitate solar water- splitting in our system, we synthesized tree-like nanowire heterostructures, consisting of silicon trunks and titanium oxide branches. Visually, arrays of these nanostructures very much resemble an artificial forest.
Source: http://newscenter.lbl.gov/

‘Magic Bullet’ For Acute Lung Injury

Researchers at Queen’s University Belfast have devised a ‘magic bullet’ nanomedicine which could become the first effective treatment for Acute Lung Injury or ALI, a condition affecting 20 per cent of all patients in intensive care. Many with the condition die as a result of lung failure.
ALI patients can become critically ill and develop problems with breathing when their lungs become inflamed and fill with fluid. The new drug, a nanoparticle, measuring around one billionth of a metre. could revolutionise clinical management of patients in intensive care units. The patient can inhale it, taking the drug directly into the lungs and to the point of inflammation. Current treatments are unable to target directly the inflammation and can result in unpleasant side effects.
lung infection
Nanoparticles are perhaps one of the most exciting new approaches to drug development. Most research in the area focuses on how the delivery of drugs to the disease site can be improved in these minute carriers. Our own research in this area focuses on how nanoparticles interact with cells and how this can be exploited to produce therapeutic effects both in respiratory disease and cancer.”, said Professor Chris Scott from the School of Pharmacy, who is leading the research.

Source: http://www.qub.ac.uk/