Tag Archives: nanotechnology

Manipulating The “Boss Gene” For Reprogramming Humans

It seems like everything is going wireless these days. That now includes efforts to reprogram the human genome. A new University at Buffalo-led study describes how researchers wirelessly controlled FGFR1 — a gene that plays a key role in how humans grow from embryos to adults — in lab-grown brain tissue. The ability to manipulate the gene, the study’s authors say, could lead to new cancer treatments, and ways to prevent and treat mental disorders such as schizophrenia.

It represents a step forward toward genetic manipulation technology that could upend the treatment of cancer, as well as the prevention and treatment of schizophrenia and other neurological illnesses. It centers on the creation of a new subfield of research the study’s authors are calling “optogenomics,” or controlling the human genome through laser light and nanotechnology.

The left image shows the gene FGFR1 in its natural state. The right image shows the gene when exposed to laser light, which causes the gene to activiate and deactivate.

The potential of optogenomic interfaces is enormous,” says co-author Josep M. Jornet, PhD, associate professor in the Department of Electrical Engineering in the UB School of Engineering and Applied Sciences. “It could drastically reduce the need for medicinal drugs and other therapies for certain illnesses. It could also change how humans interact with machines.

For the past 20 years, scientists have been combining optics and genetics — the field of optogenetics — with a goal of employing light to control how cells interact with each other. By doing this, one could potentially develop new treatments for diseases by correcting the miscommunications that occur between cells. While promising, this research does not directly address malfunctions in genetic blueprints that guide human growth and underlie many diseases. The new research begins to tackle this issue because FGFR1 — it stands for Fibroblast Growth Factor Receptor 1 — holds sway over roughly 4,500 other genes, about one-fifth of the human genome, as estimated by the Human Genome Project, says study co-author Michal K. Stachowiak.

In some respects, it’s like a boss gene,” says Stachowiak, PhD, professor in the Department of Pathology and Anatomical Sciences in the Jacobs School of Medicine and Biomedical Sciences at UB. “By controlling FGFR1, one can theoretically prevent widespread gene dysregulations in schizophrenia or in breast cancer and other types of cancer.”

The work — spearheaded by UB researchers Josep M. Jornet, Michal K. Stachowiak, Yongho Bae and Ewa K. Stachowiak — was reported in the June edition of the Proceedings of the Institute of Electrical and Electronics Engineers.

Source: http://www.buffalo.edu/

Nanobiochip Detects Minute Levels Of Disease

The difficulty in spotting minute amounts of disease circulating in the bloodstream has proven a stumbling block in the detection and treatment of cancers that advance stealthily with few symptoms. With a novel electrochemical biosensing device that identifies the tiniest signals these biomarkers emit, a pair of NJIT inventors are hoping to bridge this gap. Their work in disease detection is an illustration of the power of electrical sensing – and the growing role of engineers – in medical research.

Ideally, there would be a simple, inexpensive test – performed at a regular patient visit in the absence of specific symptoms – to screen for some of the more silent, deadly cancers,” says Bharath Babu Nunna, a recent Ph.D. graduate who worked with Eon Soo Lee, an assistant professor of mechanical engineering, to develop a nanotechnology-enhanced biochip to detect cancers, malaria and viral diseases such as pneumonia early in their progression with a pin prick blood test.

Their device includes a microfluidic channel through which a tiny amount of drawn blood flows past a sensing platform coated with biological agents that bind with targeted biomarkers of disease in body fluids such as blood, tears and urine – thereby triggering an electrical nanocircuit that signals their presence. In research recently published in Nano Covergence, Nunna and his co-authors demonstrated the use of gold nanoparticles to enhance the sensor signal response of their device in cancer detection, among other findings.

One of the device’s core innovations is the ability to separate blood plasma from whole blood in its microfluidic channels. Blood plasma carries the disease biomarkers and it is therefore necessary to separate it to enhance the “signal to noise ratio” in order to achieve a highly accurate test. The standalone device analyzes a blood sample within two minutes with no need for external equipment.

Our approach detects targeted disease biomolecules at the femto scale concentration, which is smaller than nano and even pico scale, and is akin to searching for a planet in a galaxy cluster. Current sensing technology is limited to concentrations a thousand times larger. Using a nanoscale platform allows us to identify these lower levels of disease,” Nunna says, adding, “And by separating the plasma from the blood, we are able to concentrate the disease biomarkers.”

Source: https://www.eurekalert.org/

Ruthenium-based Catalyst Outperforms Platinum To Produce Hydrogen

A novel ruthenium-based catalyst developed at UC Santa Cruz has shown markedly better performance than commercial platinum catalysts in alkaline water electrolysis for hydrogen production. The catalyst is a nanostructured composite material composed of carbon nanowires with ruthenium atoms bonded to nitrogen and carbon to form active sites within the carbon matrix.

The electrochemical splitting of water to produce hydrogen is a crucial step in the development of hydrogen as a clean, environmentally friendly fuel (for car or heating system). Much of the effort to reduce the cost and increase the efficiency of this process has focused on finding alternatives to expensive platinum-based catalysts. At UC Santa Cruz, researchers led by Shaowei Chen, professor of chemistry and biochemistry, have been investigating catalysts made by incorporating ruthenium and nitrogen into carbon-based nanocomposite materials. Their new findings, published February 7 in Nature Communications, not only demonstrate the impressive performance of their ruthenium-based catalyst but also provide insights into the mechanisms involved, which may lead to further improvements.

Electron microscopy of carbon nanowires co-doped with ruthenium and nitrogen shows ruthenium nanoparticles decorating the surface of the nanowires. Elemental mapping analysis shows individual ruthenium atoms within the carbon matrix (red arrows, below).

 

 

 

 

 

 

 

 

This is a clear demonstration that ruthenium can have remarkable activity in catalyzing the production of hydrogen from water,” Chen said. “We also characterized the material on the atomic scale, which helped us understand the mechanisms, and we can use these results for the rational design and engineering of ruthenium-based catalysts.

Electron microscopy and elemental mapping analysis of the material showed ruthenium nanoparticles as well as individual ruthenium atoms within the carbon matrix. Surprisingly, the researchers found that the main sites of catalytic activity were single ruthenium atoms rather than ruthenium nanoparticles.

Source: https://news.ucsc.edu/

How To Replace The Thick Glass Lenses by 2D Metalens

In optics, the era of glass lenses may be waning. In recent years, physicists and engineers have been designing, constructing and testing different types of ultrathin materials that could replace the thick glass lenses used today in cameras and imaging systems. Critically, these engineered lenses — known as metalenses — are not made of glass. Instead, they consist of materials constructed at the nanoscale into arrays of columns or fin-like structures. These formations can interact with incoming light, directing it toward a single focal point for imaging purposes.

But even though metalenses are much thinner than glass lenses, they still rely on “high aspect ratio” structures, in which the column or fin-like structures are much taller than they are wide, making them prone to collapsing and falling over. Furthermore, these structures have always been near the wavelength of light they’re interacting with in thickness — until now. In a paper published in the journal Nano Letters, a team from the University of Washington (UW) and the National Tsing Hua University in Taiwan announced that it has constructed functional metalenses that are one-tenth to one-half the thickness of the wavelengths of light that they focus. Their metalenses, which were constructed out of layered 2D materials, were as thin as 190 nanometers — less than 1/100,000ths of an inch thick.

This is the first time that someone has shown that it is possible to create a metalens out of 2D materials,” said senior and co-corresponding author Arka Majumdar, a UW assistant professor of physics and of electrical and computer engineering.

Their design principles can be used for the creation of metalenses with more complex, tunable features, added Majumdar, who is also a faculty researcher with the UW’s Molecular Engineering & Sciences Institute and Institute for Nano-Engineered Systems.

Source: https://www.washington.edu/

Double Layers Of Graphene Conduct Current Without Resistance

Scientists at the Helmholtz Zentrum Berlin (HZB) have found evidence that double layers of graphene have a property that may let them conduct current completely without resistance. They probed the bandstructure at BESSY II with extremely high resolution ARPES and could identify a flat area at a surprising location.

Carbon atoms have diverse possibilities to form bonds. Pure carbon can therefore occur in many forms, as diamond, graphite, as nanotubes, football molecules or as a honeycomb-net with hexagonal meshes, graphene. This exotic, strictly two-dimensional material conducts electricity excellently, but is not a superconductor. But perhaps this can be changed.

In April 2018, a group at MIT, USA, showed that it is possible to generate a form of superconductivity in a system of two layers of graphene under very specific conditions: To do this, the two hexagonal nets must be twisted against each other by exactly the magic angle of 1.1°. Under this condition a flat band forms in the electronic structure. The preparation of samples from two layers of graphene with such an exactly adjusted twist is complex, and not suitable for mass production. Nevertheless, the study has attracted a lot of attention among experts.

But there is one more, much simpler way of flat band formation. This was shown by a group at the HZB around Prof. Oliver Rader and Dr. Andrei Varykhalov with investigations at BESSY II. The samples were provided by Prof. Thomas Seyller, TU Chemnitz. There they are produced using a process that is also suitable for the production of larger areas and in large quantities: A silicon carbide crystal is heated until silicon atoms evaporate from the surface, leaving first a single-layer of graphene on the surface, and then a second layer of graphene. The two graphene layers are not twisted against each other, but lie exactly on top of each other.

This flat area is a prerequisite for superconductivity but only if it is situated exactly at the so-called Fermi energy. In the case of the two-layer graphene, its energy level is only 200 milli-electron volts below the Fermi energy, but it is possible to raise the energy level of the flat area to the Fermi energy either by doping with foreign atoms or by applying an external voltage, the so-called gate voltage.

The findings have been Published in Science Advances.

Source: https://www.helmholtz-berlin.de/

Stem Cell Therapy Could Treat Alzheimer’s And Parkinson’s

Rutgers scientists have created a tiny, biodegradable scaffold to transplant stem cells and deliver drugs, which may help treat Alzheimer’s and Parkinson’s diseases, aging brain degeneration, spinal cord injuries and traumatic brain injuriesStem cell transplantation, which shows promise as a treatment for central nervous system diseases, has been hampered by low cell survival rates, incomplete differentiation of cells and limited growth of neural connections.

So, Rutgers scientists designed bio-scaffolds that mimic natural tissue and got good results in test tubes and mice. These nano-size scaffolds hold promise for advanced stem cell transplantation and neural tissue engineering. Stem cell therapy leads to stem cells becoming neurons and can restore neural circuits.

It’s been a major challenge to develop a reliable therapeutic method for treating central nervous system diseases and injuries,” said study senior author KiBum Lee, a professor in the Department of Chemistry and Chemical Biology at Rutgers University-New Brunswick. “Our enhanced stem cell transplantation approach is an innovative potential solution.

The researchers, in cooperation with neuroscientists and clinicians, plan to test the nano-scaffolds in larger animals and eventually move to clinical trials for treating spinal cord injury. The scaffold-based technology also shows promise for regenerative medicine.

The study included researchers from Rutgers and Kyung Hee University in South Korea. The results have been published in  Nature Communications.

Source: https://www.eurekalert.org/

Swarm Of NanoRobots Can Improve The Efficiency Of Any Machine

The research team of Prof. Massimiliano Esposito of the University of Luxembourg studied the thermodynamics of  nanomachines. All machines convert one form of energy into another form – for example a car engine turns the energy stored in fuel into motion energy. Those processes of energy conversion, described by the theory called thermodynamics, don’t only take place on the macro-level of big machines, but also at the micro-level of molecular machines that drive muscles or metabolic processes and even on the atomic level. The research team of Prof. Massimiliano Esposito of the University of Luxembourg studies the thermodynamics of nanomachines only consisting of a few atoms.

In a paper published in the prestigious scientific journal Physical Review X, they outline how these small machines behave in concert. Their insights could be used to improve the energy efficiency of all kinds of machines, big or small.

Recent progress in nanotechnology has enabled researchers to understand the world in ever-smaller scales and even allows for the design and manufacture of extremely small artificial machines.

There is evidence that these machines are far more efficient than large machines, such as cars. Yet in absolute terms, the output is low compared to the needs we have in daily life applications,” explains Tim Herpich, PhD student at Esposito’s research group and main author of the paper. “That is why we studied how the nanomachines interact with each other and looked at how ensembles of those small machines behave. We wanted to see if there are synergies when they act in concert.”

The researchers found that the nanomachines under certain conditions start to arrange in “swarms” and synchronise their movements. “We could show that the synchronisation of the machines triggers significant synergy effects, so that the overall energy output of the ensemble is far greater than the sum of the individual outputs,” said Prof. Esposito. While this is basic research, the principles outlined in the paper could potentially be used to improve the efficiency of any machine in the future, the researcher explains.

In order to simulate and study the energetic behaviour of swarms of nanomachines, the scientists created mathematical models that are based on existing literature and outcomes of experimental research.

Source: https://wwwen.uni.lu/

How To Make Concrete Leaner, Greener, Stronger And More Elastic

Rice University scientists have developed micron-sized calcium silicate spheres that could lead to stronger and greener concrete, the world’s most-used synthetic material. To Rice materials scientist Rouzbeh Shahsavari and graduate student Sung Hoon Hwang, the spheres represent building blocks that can be made at low cost and promise to mitigate the energy-intensive techniques now used to make cement, the most common binder in concrete.

The researchers formed the spheres in a solution around nanoscale seeds of a common detergent-like surfactant. The spheres can be prompted to self-assemble into solids that are stronger, harder, more elastic and more durable than ubiquitous Portland cement.

Packed, micron-scale calcium silicate spheres developed at Rice University are a promising material that could lead to stronger and more environmentally friendly concrete

Cement doesn’t have the nicest structure,” said Shahsavari, an assistant professor of materials science and nanoengineering. “Cement particles are amorphous and disorganized, which makes it a bit vulnerable to cracks. But with this material, we know what our limits are and we can channel polymers or other materials in between the spheres to control the structure from bottom to top and predict more accurately how it could fracture.”

He said the spheres are suitable for bone-tissue engineering, insulation, ceramic and composite applications as well as cement.

Source: https://news.rice.edu/

Spray-On Electronic Nano-Antennas For Wearables

The promise of wearables, functional fabrics, the Internet of Things, and their “next-generation” technological cohort seems tantalizingly within reach. But researchers in the field will tell you a prime reason for their delayed “arrival” is the problem of seamlessly integrating connection technology — namely, antennas — with shape-shifting and flexible “things.”

But a breakthrough by researchers in Drexel’s College of Engineering, could now make installing an antenna as easy as applying some bug spray. In research recently published in Science Advances, the group reports on a method for spraying invisibly thin antennas, made from a type of two-dimensional, metallic material called MXene, that perform as well as those being used in mobile devices, wireless routers and portable transducers.

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Spray-applied MXene antennas could open the door for new applications in smart technology, wearables and IoT devices

This is a very exciting finding because there is a lot of potential for this type of technology,” said Kapil Dandekar, PhD, a professor of Electrical and Computer Engineering in the College of Engineering, who directs the Drexel Wireless Systems Lab, and was a co-author of the research. “The ability to spray an antenna on a flexible substrate or make it optically transparent means that we could have a lot of new places to set up networks — there are new applications and new ways of collecting data that we can’t even imagine at the moment.”

Source: https://drexel.edu/

New Solar Cells Could Harvest 85% of Visible Light

Scientists have developed a photoelectrode that can harvest 85 percent of visible light in a 30 nanometers-thin semiconductor layer between gold layers, converting light energy 11 times more efficiently than previous methods. In the pursuit of realizing a sustainable society, there is an ever-increasing demand to develop revolutionary solar cells or artificial photosynthesis systems that utilize visible light energy from the sun while using as few materials as possible. The research team, led by Professor Hiroaki Misawa of the Research Institute for Electronic Science at Hokkaido University (Japan), has been aiming to develop a photoelectrode that can harvest visible light across a wide spectral range by using gold nanoparticles loaded on a semiconductor. But merely applying a layer of gold nanoparticles did not lead to a sufficient amount of light absorption, because they took in light with only a narrow spectral range.

In the study published in Nature Nanotechnology, the research team sandwiched a semiconductor, a 30-nanometer titanium dioxide thin-film, between a 100-nanometer gold film and gold nanoparticles to enhance light absorption. When the system is irradiated by light from the gold nanoparticle side, the gold film worked as a mirror, trapping the light in a cavity between two gold layers and helping the nanoparticles absorb more light. To their surprise, more than 85 percent of all visible light was harvested by the photoelectrode, which was far more efficient than previous methods. Gold nanoparticles are known to exhibit a phenomenon called localized plasmon resonance which absorbs a certain wavelength of light.

“Our photoelectrode successfully created a new condition in which plasmon and visible light trapped in the titanium oxide layer strongly interact, allowing light with a broad range of wavelengths to be absorbed by gold nanoparticles,” says Hiroaki Misawa.

 Source: https://www.global.hokudai.ac.jp/