Articles from July 2012

NanoParticle Electric Charge Is Now Measured

Nano particles are a millionth of a millimeter in size, making them invisible to the human eye. Unless, that is, they are under the microscope of Prof. Madhavi Krishnan, a biophysicist at the University of Zurich (Switzerland). Prof. Krishnan has developed a new method that measures not only the size of the particles but also their electrostatic charge. Up until now it has not been possible to determine the charge of the particles directly. This unique method, which is the first of its kind in the world, is just as important for the manufacture of drugs as in basic research.

Put simply, particles with just a small charge make large circular movements in their traps, while those with a high charge move in small circles. This phenomenon can be compared to that of a light-weight ball which, when thrown, travels further than a heavy one. The US physicist Robert A. Millikan used a similar method 100 years ago in his oil drop experiment to determine the velocity of electrically charged oil drops. In 1923, he received the Nobel Prize in physics in recognition of his achievements. «But he examined the drops in a vacuum», Prof. Krishnan explains. «We on the other hand are examining nano particles in a solution which itself influences the properties of the particles».


Flexible Cell Phone

University of Texas  at Arlington (UT Arlington) professor Cheng Luo can envision the day that a flexible cell phone could be folded and placed in a pocket like a billfold or that a laptop computer could be rolled up and stored. Through an active $300,000 National Science Foundation grant, the mechanical and aerospace engineering professor is developing a process called “micropunching lithography.” The process is used to create lightweight, low-cost and more flexible polymer-based devices that have the potential to replace silicon-based materials commonly used in computers and other electronic devices. Luo’s work was recently published in the June 2012 North America edition of International Innovation. 

“Practical applications for these microstructures could be in everything from glucose monitoring and delivery of chemicals in treating water pipes,” Luo said. 

You can rfollow  a  similar research at the Rice University . read the article.


Photovoltaics Everywhere

Solar cells convert sunlight into electricity using semiconductor materials that exhibit the photovoltaic effect – meaning they absorb photons and release electrons that can be channeled into an electrical current. Photovoltaics are the ultimate source of clean, green and renewable energy but today’s  technologies utilize relatively scarce and expensive semiconductors. But now  High efficiency solar cells could be made from virtually any semiconductor material. This technology has been developed by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UCBerkeley. 

It’s time we put bad materials to good use,” says physicist Alex Zettl, Director of the Center of Integrated Nanomechanical Systems (COINS), who led this research along with colleague Feng Wang. “Our technology allows us to sidestep the difficulty in chemically tailoring many earth abundant, non-toxic semiconductors and instead tailor these materials simply by applying an electric field.”Our technology reduces the cost and complexity of fabricating solar cells and thereby provides what could be an important cost-effective and environmentally friendly alternative that would accelerate the usage of solar energy.”


Synthetic Nano-Engineered Vaccines

Scientists at the Biodesign Institute at Arizona State University have turned to a promising field called DNA nanotechnology to make an entirely new class of synthetic vaccines. In a study published in the journal Nano Letters, Biodesign immunologist Yung Chang joined forces with her colleagues, including DNA nanotechnology innovator Hao Yan, to develop the first vaccine complex that could be delivered safely and effectively by piggybacking onto self-assembled, three-dimensional DNA nanostructures.

When Hao treated DNA not as a genetic material, but as a scaffolding material, that made me think of possible applications in immunology,” said Chang, an associate professor in the School of Life Sciences and a researcher in they Biodesign Institute’s Center for Infectious Diseases and Vaccinology. “



1000 Times Smaller Doses To Destroy Prostate Tumor

Currently, large doses of chemotherapy are required when treating certain forms of cancer, resulting in toxic side effects. The chemicals enter the body and work to destroy or shrink the tumor, but also harm vital organs and drastically affect bodily functions. Now, University of Missouri scientists have found a more efficient way of targeting prostate tumors by using gold nanoparticles and a compound found in tea leaves. This new treatment would require doses that are thousands of times smaller than chemotherapy and do not travel through the body inflicting damage to healthy areas. The study is being published in the Proceedings of the National Academy of Science.

In our study, we found that a special compound in tea was attracted to tumor cells in the prostate,” said Kattesh Katti, curators’ professor of radiology and physics in the School of Medicine and the College of Arts and Science and senior research scientist at the MU Research Reactor. “When we combined the tea compound with radioactive gold nanoparticles, the tea compound helped ‘deliver’ the nanoparticles to the site of the tumors and the nanoparticles destroyed the tumor cells very efficiently.”
Enjoy a demonstration video>

Nanorobots To Kill Cancer

University of Florida researchers have moved a step closer to treating diseases on a cellular level by creating a tiny particle that can be programmed to shut down the genetic production line that cranks out disease-related proteins. In laboratory tests, these newly created “nanorobots” all but eradicated hepatitis C virus infection. The programmable nature of the particle makes it potentially useful against diseases such as cancer and other viral infections.

This is a novel technology that may have broad application because it can target essentially any gene we want,” said Dr. Chen Liu, professor of pathology at the University of Florida. “This opens the door to new fields so we can test many other things. We’re excited about it.

A team from MIT is working in the same direction:
See former articles:


Highly Transparent Solar Cells For Windows

UCLA researchers have developed a new transparent solar cell that is an advance toward giving windows in homes and other buildings the ability to generate electricity while still allowing people to see outside. Their study appears in the journal ACS NanoThe UCLA team describes a new kind of polymer solar cell (PSC) that produces energy by absorbing mainly infrared light, not visible light, making the cells nearly 70% transparent to the human eye. They made the device from a photoactive plastic that converts infrared light into an electrical current.

Tranparent cells
"These results open the potential for visibly transparent polymer solar cells as add-on components of portable electronics, smart windows and building-integrated photovoltaics and in other applications," said study leader Yang Yang, a UCLA professor of materials science and engineering, who also is director of the Nano Renewable Energy Center at California NanoSystems Institute (CNSI).


You Will Never Wash Your Car Again

Researchers at TU/e -Technische Universiteit in Eindhoven (Nederland) – have for the first time developed a coating with a surface that repairs itself after damage. This new coating has numerous potential applications – for example mobile phones that will remain clean from fingerprints, cars that never need to be washed, and aircraft that need less frequent repainting. The results were published in the 17 July edition of the journal Advanced Materials.

Functional coatings, for example with highly water-resistant or antibacterial properties, have at their surface nano-sized molecular groups that provide these specific properties. But up to now, these molecular groups are easily and irreversibly damaged by minor contact with their surface (such as by scratching), quickly causing their properties to be lost. This has been a big limitation to the possible applications of these coatings. Researcher Catarina Esteves of the department of Chemical Engineering and Chemistry at TU/e and her colleagues have now found a solution to this problem. 


Stem Cells That Tell Hair It’s Time to Grow

Scientists from Yale University have discovered a few month ago the source of signals that trigger hair growth, an insight that may lead to fight baldnessThe researchers identified stem cells within the skin's fatty layer and showed that molecular signals from these cells were necessary to spur hair growth in mice. "If we can get these fat cells in the skin to talk to the dormant stem cells at the base of hair follicles, we might be able to get hair to grow again," said Valerie Horsley , assistant professor of molecular, cellular and developmental biology at Yale University.

Yale researchers now  captured these images of hair follicles of a mouse, with nuclei of epithelial cells stained in green and mesenchymal cells, which are active in early development, in red. Yale scientists found that mesenchymal cells were crucial to hair growth. 




Supramolecular Nanochemistry To Fight Tumors

Researchers at Brigham and Women's Hospital (BWH), affiliate to Harvard Medical School,  are the first to report a new approach that integrates rational drug design with supramolecular nanochemistry in cancer treatment. Supramolecular chemistry is the development of complex chemical systems using molecular building blocks. The researchers utilized such methods to create nanoparticles that significantly enhanced antitumor activity with decreased toxicity in breast and ovarian cancer models


"This work is effectively moving beyond using nanotechnology as drug 'delivery' vehicles to reengineering drugs themselves so that they become nanomedicines." said Shiladitya Sengupta, PhD, MSc, BWH associate bioengineer, and senior study author . 


Molecular Memory for Smartphones

How to raise the RAM memory limits of smartphones and tablets that limit the number of applications that can be run  at on time?  Elad Mentovich, a Ph.D. student at Tel Aviv University, has made a vertical transistor based on a single carbon-60 molecule that he reckons could be the basis for both a logic transistor and a memory element. Major companies in the memory industry have already expressed interest in the technology, said Mentovich, 

Because the memory is a based on a single molecule of carbon in a spherical form it can be as small as one-nanometer in diameter, making it a candidate for post-CMOS integration. The molecular memory is ready to produced in existing wafer fabs Mentovich asserts. This new type of carbon-based transistors ramps up speed and memory for mobile devices.


Hazard of Nano-Engineered Products

Zinc oxide would be the perfect sunscreen ingredient if the product didn't look quite so silly. Thick, white and pasty, it was once seen mostly on lifeguards, surfers and others who needed serious protection. But when sunscreens are made with nanoparticles, the tiniest substances that humans can engineer, they turn clear — which makes them more user-friendly.Sunscreen is just one of the many uses of nanotechnology, which drastically shrinks and fundamentally changes the structure of chemical compounds, but products made with nanomaterials also raise largely unanswered safety questions — such as whether the particles that make them effective can be absorbed into the bloodstream and are toxic to living cells.

We haven't characterized these materials very well yet in terms of what the potential impacts on living organisms could be,” said Kathleen Eggleson, a research scientist at the Center for Nanoscience and Technology at the University of Notre Dame.Scientists don't yet know how long nanoparticles stay in the human body or what they might do there. Animal research has found that inhaled nanoparticles can reach all areas of the respiratory tract; because of their small size and shape, they can migrate quickly into cells and organs.The smaller particles may pose risks to the heart and blood vessels, .Still unknown is “how significant (potential damage) would be, how much nanomaterial would be needed to cause appreciable harm, and how well the body would be able to deal with the material and recover,” said Andrew Maynard, director of the University of Michigan Risk Science Center.