Nanofibers twisted together to create structures tougher than bullet proof vests


Researchers at the University of Texas at Dallas have created new structures that exploit the electromechanical properties of specific nanofibers to stretch to up to seven times their length, while remaining tougher than Kevlar.

Testing-the-Bullet-Proof-Vest

The Science and the Materials have come a very long way!
These structures absorb up to 98 joules per gram. Kevlar, often used to make bulletproof vests, can absorb up to 80 joules per gram. The material can reinforce itself at points of high stress and could potentially be used in military airplanes or other defense applications.

In a study published by ACS Applied Materials and Interfaces, a journal of the American Chemical Society, researchers twisted nanofiber into yarns and coils. The electricity generated by stretching the twisted nanofiber formed an attraction 10 times stronger than a hydrogen bond, which is considered one of the strongest forces formed between molecules.

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Dr. Majid Minary, an assistant professor of mechanical engineering, was senior author of the study.
Credit: Image courtesy of University of Texas, Dallas

Researchers sought to mimic their earlier work on the piezoelectric action (how pressure forms electric charges) of collagen fibers found inside bone in hopes of creating high-performance materials that can reinforce itself, said Dr. Majid Minary, an assistant professor of mechanical engineering in UT Dallas’ Erik Jonsson School of Engineering and Computer Science and senior author of the study.

“We reproduced this process in nanofibers by manipulating the creation of electric charges to result in a lightweight, flexible, yet strong material,” said Minary, who is also a member of the Alan G. MacDiarmid NanoTech Institute. “Our country needs such materials on a large scale for industrial and defense applications.”

For their experiment, researchers first spun nanofibers out of a material known as polyvinylidene fluoride (PVDF) and its co-polymer, polyvinvylidene fluoride trifluoroethylene (PVDF-TrFE).

Researchers then twisted the fibers into yarns, and then continued to twist the material into coils.

“It’s literally twisting, the same basic process used in making conventional cable,” Minary said.

Researchers then measured mechanical properties of the yarn and coils such as how far it can stretch and how much energy it can absorb before failure.

“Our experiment is proof of the concept that our structures can absorb more energy before failure than the materials conventionally used in bulletproof armors,” Minary said. “We believe, modeled after the human bone, that this flexibility and strength comes from the electricity that occurs when these nanofibers are twisted.”

The next step in the research is to make larger structures out of the yarns and coils, Minary said.

Other UT Dallas authors on the paper are Mahmoud Baniasadi, Zhe Xu, Yang Xi and Salvador Moreno, all research assistants in the Jonsson School; alumnus Jiacheng Huang; Jason Chang, a biomedical engineering senior; and Dr. Manuel Quevedo-Lopez, professor of materials science and engineering. Dr. Mohammad Naraghi, an assistant professor of aerospace engineering at Texas A&M University, also participated in the work.

The work was funded by the Air Force Office of Scientific Research Young Investigator Research Programand the National Science Foundation.


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The above story is based on materials provided by University of Texas, Dallas. Note: Materials may be edited for content and length.

Novel nanoparticle therapy promotes wound healing


Burns Nano 032715 150326121951-largeAn experimental therapy developed by researchers at Albert Einstein College of Medicine of Yeshiva University cut in half the time it takes to heal wounds compared to no treatment at all. Details of the therapy, which was successfully tested in mice, were published online in the Journal of Investigative Dermatology.

“We envision that our nanoparticle therapy could be used to speed the healing of all sorts of wounds, including everyday cuts and burns, surgical incisions, and chronic skin ulcers, which are a particular problem in the elderly and people with diabetes,” said study co-leader David J. Sharp, Ph.D., professor of physiology & biophysics at Einstein.

Dr. Sharp and his colleagues had earlier discovered that an enzyme called fidgetin-like 2 (FL2) puts the brakes on skin cells as they migrate towards wounds to heal them. They reasoned that the healing cells could reach their destination faster if their levels of FL2 could be reduced. So they developed a drug that inactivates the gene that makes FL2 and then put the drug in tiny gel capsules called nanoparticles and applied the nanoparticles to wounds on mice. The treated wounds healed much faster than untreated wounds.

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Imaging of burns indicates that those treated with the FL2 inhibitor nanotechnology experienced collagen deposition and hair follicle formation. (2-photo confocal microscopy)
Credit: Vera DesMarais/Albert Einstein College of Medicine

FL2 belongs to the fidgetin family of enzymes, which play varying roles in cellular development and function. To learn more about FL2’s role in humans, Dr. Sharp suppressed FL2’s activity in human cells in tissue culture. When those cells were placed on a standard wound assay (for measuring properties like cell migration and proliferation), they moved unusually fast. “This suggested that if we could find a way to target FL2 in humans, we might have a new way to promote wound healing,” said Dr. Sharp.

Dr. Sharp and project co-leader Joshua Nosanchuk, M.D., professor of medicine at Einstein and attending physician, infectious diseases at Montefiore Medical Center, developed a wound-healing therapy that uses molecules of silencing RNA (siRNAs) specific for FL2. The siRNAs act to silence genes. They do so by binding to a gene’s messenger RNA (mRNA), preventing the mRNA from being translated into proteins (in this case, the enzyme FL2). However, “siRNAs on their own won’t be effectively taken up by cells, particularly inside a living organism” said Dr. Sharp. “They will be quickly degraded unless they are put into some kind of delivery vehicle.”

To find a way to deliver siRNAs for curbing FL2, Dr. Sharp collaborated with Joel Friedman, M.D., Ph.D., professor of physiology & biophysics and of medicine at Einstein, and study co-leader Adam Friedman, M.D., director of dermatologic research at Einstein and Montefiore, who together had developed nanoparticles that protect molecules such as siRNA from being degraded as they ferry the molecules to their intended targets.

The nanoparticles with their siRNA cargoes were then tested by topically applying them to mice with either skin excisions or burns. In both cases, the wounds closed more than twice as fast as in untreated controls. “Not only did the cells move into the wounds faster, but they knew what to do when they got there,” said Dr. Sharp. “We saw normal, well-orchestrated regeneration of tissue, including hair follicles and the skin’s supportive collagen network.”

Dr. Sharp plans to start testing the therapy on pigs, whose skin closely resembles that of humans, within months.


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The above story is based on materials provided by Albert Einstein College of Medicine of Yeshiva University. Note: Materials may be edited for content and length.

Surface-modified Nanoparticles Endow Coatings with Combine Properties


buckyballNanoparticles are specifically adapted to the particular application by Small Molecule Surface Modification (SMSM). Thereby surfaces of work pieces or moldings are expected to exhibit several different functions at one and the same time.

Fabricators and processors alike demand consistently high quality for their intermediate and final products. The properties of these goods usually also have to meet specific requirements.

Particularly the surfaces of work pieces or moldings are expected to exhibit several different functions at one and the same time, depending on the industry.

Robustness, unchanging appearance, mar resistance, impact resistance or UV stability may be required, for instance. The INM – Leibniz Institute for New Materials uses nanoparticles as design element for such multifunctional coatings. These nanoparticles are specifically adapted to the particular application by Small Molecule Surface Modification (SMSM).

Depending on which property is desired, the nanoparticles used can be surface modified with organic moieties. Small Molecule Surface Modification (SMSM) bestows specific combinations of desired properties, for example hydrophilic, hydrophobic, adhesive, anti-adhesive, acidic, basic, inert or polymerizable.

Nanoparticles thus modified are used to develop nanocomposites: they combine the physical solid-state properties of e.g. ceramics or semiconductors with classic polymer-processing technology. Titanium dioxide, barium titanate, indium-tin oxide or zirconium dioxide, for instance, are used as nanoparticles. In addition to the chemical intrinsic composition of the nanoparticles and their SMSM surface treatment, the properties that are attainable for the desired coatings also vary with the size and dispersal mode of the nanoparticles.

INM’s composite systems are produced via wet-chemical processes. The modified nanoparticles and additives combine with a polymer matrix (an epoxy resin, an acrylate, a polyimide for example) or a hybrid matrix (organic-inorganic) to produce a coatable Nanomer composite system.

“The modular principle makes it possible to achieve a number of properties at one and the same time in one material,” explains Carsten Becker-Willinger, head of the program division Nanomers, “it helps us to respond in a highly systematic way to the different needs of industry,” the chemist summarizes the potential of nanocomposite technology.

Source: Leibniz Institute for New Materials

Oak Ridge National Laboratory and DOE: Desalination with a Nanoporous Graphene Membrane


Graphene Nanonporous Mem ornlledteamdLess than 1 percent of Earth’s water is drinkable. Removing salt and other minerals from our biggest available source of water—seawater—may help satisfy a growing global population thirsty for fresh water for drinking, farming, transportation, heating, cooling and industry. But desalination is an energy-intensive process, which concerns those wanting to expand its application.

Now, a team of experimentalists led by the Department of Energy’s Oak Ridge National Laboratory has demonstrated an energy-efficient desalination technology that uses a porous made of strong, slim graphene—a carbon honeycomb one atom thick. The results are published in the March 23 advance online issue of Nature Nanotechnology.

“Our work is a proof of principle that demonstrates how you can desalinate saltwater using free-standing, porous graphene,” said Shannon Mark Mahurin of ORNL’s Chemical Sciences Division, who co-led the study with Ivan Vlassiouk in ORNL’s Energy and Transportation Science Division.

“It’s a huge advance,” said Vlassiouk, pointing out a wealth of travels through the porous graphene membrane. “The flux through the current graphene membranes was at least an order of magnitude higher than [that through] state-of-the-art polymeric membranes.”

Current methods for purifying water include distillation and reverse osmosis. Distillation, or heating a mixture to extract volatile components that condense, requires a significant amount of energy. Reverse osmosis, a more energy-efficient process that nonetheless requires a fair amount of energy, is the basis for the ORNL technology.

Making pores in the graphene is key. Without these holes, water cannot travel from one side of the membrane to the other. The water molecules are simply too big to fit through graphene’s fine mesh. But poke holes in the mesh that are just the right size, and water molecules can penetrate. Salt ions, in contrast, are larger than and cannot cross the membrane. The allows osmosis, or passage of a fluid through a semipermeable membrane into a solution in which the solvent is more concentrated. “If you have saltwater on one side of a porous membrane and freshwater on the other, an osmotic pressure tends to bring the water back to the saltwater side. But if you overcome that, and you reverse that, and you push the water from the saltwater side to the freshwater side—that’s the reverse osmosis process,” Mahurin explained.

Graphene Nanonporous Mem ornlledteamd

Researchers created nanopores in graphene (red, and enlarged in the circle to highlight its honeycomb structure) that are stabilized with silicon atoms (yellow) and showed their porous membrane could desalinate seawater. Orange represents a …more

Today reverse-osmosis filters are typically polymers. A filter is thin and resides on a support. It takes significant pressure to push water from the saltwater side to the freshwater side. “If you can make the membrane more porous and thinner, you can increase the flux through the membrane and reduce the pressure requirements, within limits,” Mahurin said. “That all serves to reduce the amount of energy that it takes to drive the process.”

Graphene to the rescue Graphene is only one-atom thick, yet flexible and strong. Its mechanical and chemical stabilities make it promising in membranes for separations. A porous graphene membrane could be more permeable than a , so separated water would drive faster through the membrane under the same conditions, the scientists reasoned. “If we can use this single layer of graphene, we could then increase the flux and reduce the membrane area to accomplish that same purification process,” Mahurin said.

To make graphene for the membrane, the researchers flowed methane through a tube furnace at 1,000 degrees C over a copper foil that catalyzed its decomposition into carbon and hydrogen. The chemical vapor deposited carbon atoms that self-assembled into adjoining hexagons to form a sheet one atom thick.

The researchers transferred the graphene membrane to a silicon nitride support with a micrometer-sized hole. Then the team exposed the graphene to an oxygen plasma that knocked carbon atoms out of the graphene’s nanoscale chicken wire lattice to create pores. The longer the graphene membrane was exposed to the plasma, the bigger the pores that formed, and the more made.

The prepared membrane separated two water solutions—salty water on one side, fresh on the other. The silicon nitride chip held the graphene membrane in place while water flowed through it from one chamber to the other. The membrane allowed rapid transport of water through the membrane and rejected nearly 100 percent of the salt ions, e.g., positively charged sodium atoms and negatively charged chloride atoms.

To figure out the best pore size for desalination, the researchers relied on the Center for Nanophase Materials Sciences (CNMS), a DOE Office of Science User Facility at ORNL. There, aberration-corrected scanning transmission electron microscopy (STEM) imaging, led by Raymond Unocic, allowed for atom-resolution imaging of graphene, which the scientists used to correlate the porosity of the graphene membrane with transport properties. They determined the optimum pore size for effective desalination was 0.5 to 1 nanometers, Mahurin said.

They also found the optimal density of pores for desalination was one pore for every 100 square nanometers. “The more pores you get, the better, up to a point until you start to degrade any mechanical stability,” Mahurin said.

Vlassiouk said making the porous membranes used in the experiment is viable on an industrial scale, and other methods of production of the pores can be explored. “Various approaches have been tried, including irradiation with electrons and ions, but none of them worked. So far, the oxygen plasma approach worked the best,” he added. He worries more about gremlins that plague today’s reverse osmosis membranes—growths on membrane surfaces that clog them (called “biofouling”) and ensuring the mechanical stability of a membrane under pressure.

Explore further: Imperfect graphene opens door to better fuel cellsus-graphene-membrane.html#jCp

MIT Analysis: Solar Photovoltaic Power “One of Few” LC Renewables” that are both Scalable and Technologically Ready to Meet Global Demand


MIT-FuturePV-01x250(From R & D Magazine)  Use of solar photovoltaics has been growing at a phenomenal rate: Worldwide installed capacity has seen sustained growth averaging 43% per year since 2000. To evaluate the prospects for sustaining such growth, the MIT researchers look at possible constraints on materials availability, and propose a system for evaluating the many competing approaches to improved solar-cell performance.

In a broad new assessment of the status and prospects of solar photovoltaic technology, Massachusetts Institute of Technology (MIT) researchers say that it is “one of the few renewable, low-carbon resources with both the scalability and the technological maturity to meet ever-growing global demand for electricity.”

The analysis is presented in Energy & Environmental Science; a broader analysis of solar technology, economics and policy will be incorporated in a forthcoming assessment of the future of solar energy by the MIT Energy Initiative.

The team comprised MIT professors Vladimir Bulović, Tonio Buonassisi and Robert Jaffe, and graduate students Joel Jean and Patrick Brown. One useful factor in making meaningful comparisons among new photovoltaic technologies, they conclude, is the complexity of the light-absorbing material.

The report divides the many technologies under development into three broad classes: wafer-based cells, which include traditional crystalline silicon, as well as alternatives such as gallium arsenide; commercial thin-film cells, including cadmium telluride and amorphous silicon; and emerging thin-film technologies, which include perovskites, organic materials, dye-sensitized solar cells and quantum dots.

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Illustration shows the MIT team’s proposed scheme for comparing different photovoltaic materials, based on the complexity of their basic molecular structure. The complexity increases from the simplest material, pure silicon (single atom, lower left), to the most complex material currently being studied for potential solar cells, quantum dots (molecular structure at top right). Materials shown in between include gallium aresenide, perovskite and dye-sensitized solar cells. Image courtesy of the researchers.

With the recent evolution of solar technology, says Jean, the paper’s lead author, it’s important to have a uniform framework for assessment. It may be time, he says, to re-examine the traditional classification of these technologies, generally into three areas: silicon wafer-based cells, thin-film cells and “exotic” technologies with high theoretical efficiencies.

“We’d like to build on the conventional framework,” says Jean, a doctoral student in MIT’s Dept. of Electrical Engineering and Computer Science. “We’re seeking a more consistent way to think about the wide range of current photovoltaic technologies and to evaluate them for potential applications. In this study, we chose to evaluate all relevant technologies based on their material complexity.”

Under this scheme, traditional silicon—a single-element crystalline material—is the simplest material. While crystalline silicon is a mature technology with advantages including high efficiency, proven reliability and no material scarcity constraints, it also has inherent limitations: Silicon is not especially efficient at absorbing light, and solar panels based on silicon cells tend to be rigid and heavy. At the other end of the spectrum are perovskites, organics and colloidal quantum dots, which are “highly complex materials, but can be much simpler to process,” Jean says.

The authors make clear that their definition of material complexity as a key parameter for comparison does not imply any equivalency with complexity of manufacturing. On the contrary, while silicon is the simplest solar-cell material, silicon wafer and cell production is complex and expensive, requiring extraordinary purity and high temperatures.

By contrast, while some complex nanomaterials involve intricate molecular structures, such materials can be deposited quickly and at low temperatures onto flexible substrates. Nanomaterial-based cells could even be transparent to visible light, which could open up new applications and enable seamless integration into windows and other surfaces. The authors caution, however, that the conversion efficiency and long-term stability of these complex emerging technologies is still relatively low. As they write in the paper: “The road to broad acceptance of these new technologies in conventional solar markets is inevitably long, although the unique qualities of these evolving solar technologies—lightweight, paper-thin, transparent—could open entirely new markets, accelerating their adoption.”

The study does caution that the large-scale deployment of some of today’s thin-film technologies, such as cadmium telluride and copper indium gallium diselenide, may be severely constrained by the amount of rare materials that they require. The study highlights the need for novel thin-film technologies that are based on Earth-abundant materials.

The study identifies three themes for future research and development. The first is increasing the power-conversion efficiency of emerging photovoltaic technologies and commercial modules.

A second research theme is reducing the amount of material needed per cell. Thinner, more flexible films and substrates could reduce cell weight and cost, potentially opening the door to new approaches to photovoltaic module design.

A third important research theme is reducing the complexity and cost of manufacturing. Here the researchers emphasize the importance of eliminating expensive, high-temperature processing, and encouraging the adoption of roll-to-roll coating processes for rapid, large-scale manufacturing of emerging thin-film technologies.

“We’ve looked at a number of key metrics for different applications,” Jean says. “We don’t want to rule out any of the technologies,” he says—but by providing a unified framework for comparison, he says, the researchers hope to make it easier for people to make decisions about the best technologies for a given application.

Source: Massachusetts Institute of Technology

Water is Our World: World Water Day 2015: Video


Surfer at Peahi Bay on Maui, HawaiiGENESIS NANOTECHNOLOGY, INC. (GNT™) is an innovative new model of NanoTechnology commercialization. Using our Proprietary Business and Technology Development Model, we harness the power of early stage NanoTechnology innovations and position them for market entry to make positive environmental and economic impacts.

Industry and Market Leaders have recognized (and are actively seeking) the competitive advantage, the superior performance properties, cost savings, flexible manufacturing platform and warranty-life advantages of nanomaterials, GNT exploits  both the technologies and the market needs to create successful commercialization models.

We are helping move Emerging Nanotechnologies to the commercialization phase by partnering and funding latter stages of research at universities across North America and Internationally.

At Genesis NanoTechnology we are developing some very exciting technologies that have the potential to be not only “commercially viable disruptive game changers” but will also create a better quality of our life on our planet.

Follow Our Blog ~ “Great Things from Small Things” at:

https://genesisnanotech.wordpress.com

Published on Mar 8, 2015

If you think about it, water links to almost everything in the world. Health. Nature. Urbanization. Industry. Energy. Food. Equality.

In 2015, the world will agree on how we want to shape our sustainable future. And for this future to happen we need water and sanitation. Learn more at http://www.worldwaterday.org

Silver Nanoparticles Could Give Millions Microbe-free Drinking Water


Silver Nano P clean-drinking-water-indiaChemists at the Indian Institute of Technology Madras have developed a portable, inexpensive water filtration system that is twice as efficient as existing filters. The filter doubles the well-known and oft-exploited antimicrobial effects of silver by employing nanotechnology. The team, led by Professor Thalappil Pradeep, plans to use it to bring clean water to underserved populations in India and beyond.

Left alone, most water is teeming with scary things. A recent study showed that your average glass of West Bengali drinking water might contain E. coli, rotavirus, cryptosporidium, and arsenic. According to the World Health Organization, nearly a billion people worldwide lack access to clean water, and about 80% of illnesses in the developing world are water-related. India in particular has 16% of the world’s population and less than 3% of its fresh water supply. Ten percent of India’s population lacks water access, and every day about 1,600 people die of diarrhea, which is caused by waterborne microbes.

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Microbe-free drinking water is hard to come by in many areas of India.

Pradeep has spent over a decade using nanomaterials to chemically sift these pollutants out. He started by tackling endosulfan, a pesticide that was hugely popular until scientists determined that it destroyed ozone and brain cells in addition to its intended insect targets. Endosulfan is now banned in most places, but leftovers persist in dangerous amounts. After a bout of endosulfan poisoning in the southwest region of Kerala, Pradeep and his colleagues developed a drinking water filter that breaks the toxin down into harmless components. They licensed the design to a filtration company, who took it to market in 2007. It was “the first nano-chemistry based water product in the world,” he says.

But Pradeep wanted to go bigger. “If pesticides can be removed by nanomaterials,” he remembers thinking, “can you also remove microbes without causing additional toxicity?” For this, Pradeep’s team put a new twist on a tried-and-true element: silver.

Silver’s microbe-killing properties aren’t news—in fact, people have known about them for centuries, says Dr. David Barillo, a trauma surgeon and the editor of a recent silver-themed supplement of the journal Burns.

“Alexander the Great stored and drank water in silver vessels when going on campaigns” in 335 BC, he says, and 19th century frontier-storming Americans dropped silver coins into their water barrels to suppress algae growth. During the space race, America and the Soviet Union both developed silver-based water purification techniques (NASA’s was “basically a silver wire sticking in the middle of a pipe that they were passing electricity through,” Barillo says). And new applications keep popping up: Barillo himself pioneered the use of silver-infused dressings to treat wounded soldiers in Afghanistan. “We’ve really run the gamut—we’ve gone from 300 BC to present day, and we’re still using it for the same stuff,” he says.

No one knows exactly how small amounts of silver are able to kill huge swaths of microbes. According to Barillo, it’s probably a combination of attacks on the microbe’s enzymes, cell wall, and DNA, along with the buildup of silver free radicals, which are studded with unpaired electrons that gum up cellular systems. These microbe-mutilating strategies are so effective that they obscure our ability to study them, because we have nothing to compare them to. “It’s difficult to make something silver-resistant, even in the lab where you’re doing it intentionally,” Barillo says.

But unlike equal-opportunity killers like endosulfan, silver knocks out the monsters and leaves the good guys alone. In low concentrations, it’s virtually harmless to humans. “It’s not a carcinogen, it’s not a mutagen, it’s not an allergen,” Barillo says. “It seems to have no purpose in human physiology—it’s not a metal that we need to have in our bodies like copper or magnesium. But it doesn’t seem to do anything bad either.”

Though silver’s mysterious germ-killing properties are old news, Pradeep is taking advantage of them in new ways. The particles his team works with are less than 50 nanometers long on any one side—about four times smaller than the smallest bacteria. Working at this level allows him greater control over desired chemical reactions, and the ability to fine-tune his filters to improve efficiency or add specific effects. Two years ago, his team developed their biggest hit yet—a combination filter that kills microbes with silver and breaks down chemical toxins with other nanoparticles. It’s portable, works at room temperature, and doesn’t require electricity. Pradeep is working with the government to make these filters available to underserved communities. Currently 100,000 households have them; “by next year’s end,” he hopes, “it will reach 600,000 people.”

The latest filter goes one better: it “tunes” the silver with carbonate, a negatively-charged ion that strips protective proteins from microbe cell membranes. This leaves the microbes even more vulnerable to silver’s attack. “In the presence of carbonate, silver is even more effective,” he explains, so he can use less of it: “Fifty parts per billion can be brought down to [25].” Unlike the earlier filter, this one kills viruses, too—good news, since according to the National Institute of Virology, most do not.

Going from 50 parts per billion of silver to 25 may not seem like a huge leap. But for Pradeep—who aims to help a lot of people for a long time—every little bit counts. Filters that contain less silver are less expensive to produce. This is vital if you want to keep costs low enough for those who need them most to buy them, or to entice the government into giving them away. He estimates that one of his new filter units will cost about $2 per year, proportionately less than what the average American pays for water.

Using less silver also improves sustainability. “Globally, silver is the most heavily used nanomaterial,” Pradeep says, and it’s not renewable: anything we use “is lost for the world.” If all filters used his carbonate trick, he points out, we could make twice as many of them before we run out of raw materials—and even more if, as he hopes, his future tunings bring the necessary amount down further. This will become especially important if his filters catch on in other places with no infrastructure and needy populations. “Ultimately, I want to use the very minimum quantity of silver,” he says.

“Pradeep’s work shows enormous potential,” says Dr. Theresa Dankovich, a water filtration expert at the University of Virginia’s Center for Global Health. But, she points out, “carbonate anions are naturally occurring in groundwater and surface waters,” so “it warrants further study to determine how they are already enhancing the effect of silver ions and silver nanoparticles,” even without purposeful manipulation by chemists. Others see potential shortcomings. James Smith, a professor of environmental engineering at the University of Virginia and the inventor of a nanoparticle-coated clay filtering pot, worries that the nanotech-heavy production process “would not allow for manufacturing in a developing world setting,” especially if Pradeep’s continuous tweaking of the model deters large-scale companies from actually producing it.

Nevertheless, Pradeep plans to continue scaling up. “If you can provide clean water, you have provided a solution for almost everything,” he says. When you have the lessons of history and the technology of the future, why settle for anything less?

Rice U. Researchers Fine-Tune Quantum Dots from Coal


Genesis Nanotechnology

rice QD finetuneGraphene quantum dots made from coal, introduced in 2013 by the Rice University lab of chemist James Tour, can be engineered for specific semiconducting properties in either of two single-step processes.

In a new study this week in the American Chemical Society journal Applied Materials & Interfaces, Tour and colleagues demonstrated fine control over the graphene oxide dots’ size-dependent band gap, the property that makes them semiconductors. Quantum dots are semiconducting materials that are small enough to exhibit quantum mechanical properties that only appear at the nanoscale.

Tour’s group found they could produce quantum dots with specific semiconducting properties by sorting them through ultrafiltration, a method commonly used in municipal and industrial water filtration and in food production.

The other single-step process involved direct control of the reaction temperature in the oxidation process that reduced coal to quantum dots. The researchers found hotter temperatures produced smaller dots, which had…

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Harvard University: Adaptive-Micro-Fluidic Sorting System: Applications: Medical Diagnostics, Desalination?


Harvard Bio 032415 id39519Employing an ingenious microfluidic design that combines chemical and mechanical properties, a team of Harvard scientists has demonstrated a new way of detecting and extracting biomolecules from fluid mixtures. The approach requires fewer steps, uses less energy, and achieves better performance than several techniques currently in use and could lead to better technologies for medical diagnostics and chemical purification.
The biomolecule sorting technique was developed in the laboratory of Joanna Aizenberg, Amy Smith Berylson Professor of Materials Science at Harvard School of Engineering and Applied Sciences (SEAS) and Professor in the Department of Chemistry and Chemical Biology. Aizenberg is also co-director of the Kavli Institute for Bionano Science and Technology and a core faculty member at Harvard’s Wyss Institute for Biologically Inspired Engineering, leading the Adaptive Materials Technologies platform there.
Capture and release of specific target biomolecules
Capture and release of specific target biomolecules from an ingoing solution mixture in a microfluidic system occurs by the concerted, dynamic and reversible action of hydrogel volume change and aptamer bind-and-release through changes in solution pH. (Image courtesy of Ankita Shastri and Ximin He)

The new microfluidic device, described in a paper appearing today in the journal (“An aptamer-functionalized chemomechanically modulated biomolecule catch-and-release system”), is composed of microscopic “fins” embedded in a hydrogel that is able to respond to different stimuli, such as temperature, pH, and light. Special DNA strands called aptamers, that under the right conditions bind to a specific target molecule, are attached to the fins, which move the cargo between two chemically distinct environments. Modulating the pH levels of the solutions in those environments triggers the aptamers to “catch” or “release” the target biomolecule.

After using computer simulations to test their novel approach, in collaboration with Prof. Anna C. Balazs from the University of Pittsburgh, Aizenberg’s team conducted proof-of-concept experiments in which they successfully separated thrombin, an enzyme in blood plasma that causes the clotting of blood, from several mixtures of proteins. Their research suggests that the technique could be applicable to other biomolecules, or used to determine chemical purity and other characteristics in inorganic and synthetic chemistry.
“Our adaptive hybrid sorting system presents an efficient chemo-mechanical transductor, capable of highly selective separation of a target species from a complex mixture–all without destructive chemical modifications and high-energy inputs,” Aizenberg said. “This new approach holds promise for the next-generation, energy-efficient separation and purification technologies and medical diagnostics.”
The system is dynamic; its integrated components are highly tunable. For example, the chemistry of the hydrogel can be modified to respond to changes in temperature, light, electric and magnetic fields, and ionic concentration. Aptamers, meanwhile, can target a range of proteins and molecules in response to variations in pH levels, temperature, and salt.
“The system allows repeated processing of a single input solution, which enables multiple recycling and a high rate of capture of the target molecules,” said lead author Ximin He, Assistant Professor of Materials Science and Engineering at Arizona State University and formerly a postdoctoral research fellow in Aizenberg’s group at Harvard.
Conventional biomolecule sorting systems rely on external electric fields, infrared radiation, and magnetic fields, and often require chemical modifications of the biomolecules of interest. That means setups can be used only once or require a series of sequential steps. In contrast, said Ankita Shastri, a graduate student in Chemistry and Chemical Biology at Harvard and a member of Aizenberg’s group, the new catch-transport-and-release system “is more efficient–requiring minimal steps and less energy, and effective–achieving recovery of almost all of the target biomolecule through its continuous reusability.”
The authors say that the system could provide a means of removing contaminants from water–and even be tailored to enable energy-efficient desalination of seawater. It could also be used to capture valuable minerals from fluid mixtures.
Source: Harvard University

Read more: Catching and releasing tiny molecules

University of Waterloo: AmorChem Closes Nanotechnology-Drug Delivery Deal


AmorChem Nanotechnology-300x200Summary: University of Waterloo and AmorChem

AmorChem has closed its first transaction with the University of Waterloo. The project focuses on a mucoadhesive nanotechnology platform that supports the delivery of drugs, which is derived from the research work of Dr. Frank Gu. AmorChem said it will partner with Dr. Gu to pursue the preclinical development of a first product delivered using the technology. Based in Montréal, AmorChem is managed by Canadian venture capital firm GeneChem. The fund invests in R&D-stage initiatives to enable pre-clinical proof-of-concept in a semi-virtual mode.

AmorChem invests in a mucoadhesive nanoparticle drug delivery platform

Montreal, February 11, 2015 – AmorChem is pleased to announce the closing of a first transaction with the University of Waterloo. The project focuses on the use of a platform technology derived from the work of Dr. Frank Gu, Canada Research Chair in Nanotechnology Engineering, and Associate Professor in the Department of Chemical Engineering at the University of Waterloo. This mucoadhesive nanotechnology platform facilitates a directed and more efficacious delivery of drugs.

AmorChem will join forces with Dr. Gu in order to pursue the preclinical development of a first product delivered using this mucoadhesive nanoparticle technology. The choice of dry eye as an indication was driven by data which convinced us that delivering drug using these nanoparticles offers advantages which could improve the treatment of this disease,” explains Inès Holzbaur, general partner at AmorChem.

The nanoparticles bind to mucous membranes, allowing for targeted delivery of the treatment payload over a prolonged period of time. The size of the particles, combined with their mucoadhesive properties, make it possible to deliver large payloads that are released in a controlled manner while resisting the ocular clearance which typically occurs by drainage and tearing. It is expected that this will offer a treatment that is less toxic and allows for better compliance. Cyclosporin A, a drug known to be useful in the treatment of dry eye, will be the first molecule to be tested using this delivery system. Although this particular project is focused on an ophthalmic indication, the platform is also suited to nasal, pulmonary and gastro-intestinal delivery.

”Supported by commercialization leadership from the Waterloo Commercialisation Office, this is a strong validation of Dr. Gu’s translational research impact and the strength of nanotechnology engineering in general at the University of Waterloo. We believe AmorChem’s investment, under its flexible and supportive business model, will pave the way to successful commercialization of this transformative technology,” says D. Georges Dixon, vicepresident, research, University of Waterloo.

“Although AmorChem focuses on investments in the province of Quebec, this collaboration with an Ontarian institution shows that the AmorChem model is adaptable to other regions, and that there is demand for our kind of translational investing outside Quebec. We believe that out-of-province opportunities could play an interesting role in the future activities of AmorChem. For example, investments in platforms such as Dr. Gu’s may allow us to start-up companies in collaboration with Quebec-based venture capital funds,” concludes Elizabeth Douville, general partner at AmorChem.

ABOUT AMORCHEM L.P. AmorChem L.P. (www.amorchem.com) is a venture capital fund located in Montreal focused on primarily investing in promising life science projects originating from Quebec-based universities and research centres. The principal limited partners of this fund are Investissement-Québec, FIER Partenaires, Fonds de solidarité FTQ and Merck & Co. This fund is the latest addition to the GeneChem portfolio of funds, a fund manager in existence since 1997. AmorChem’s innovative business model involves financing research-stage projects to enable them to reach pre-clinical proof-of-concept (“POC”) in a semi-virtual mode within 18-24 months. The fund seeks to generate returns through a two-pronged exit strategy: sell projects having reached POC to large biotechnology or pharmaceutical companies; or bundle them into new spin-out companies. AmorChem using external resources will manage the projects. To that effect, AmorChem has established a strategic partnership with the Biotechnology Research Institute in order to access its R&D platforms. In addition, to enabling projects requiring small molecules as tools or drug leads, AmorChem has founded NuChem Therapeutics Inc., a medicinal chemistry contract-research company.