Posts belonging to Category nanopore

Paper Filter Removes Harmful Viruses From Water

A simple paper sheet made by scientists at Uppsala University can improve the quality of life for millions of people by removing resistant viruses from water. The sheet, made of cellulose nanofibers, is called the mille-feuille filter as it has a unique layered internal architecture resembling that of the French puff pastry mille-feuille (Eng. thousand leaves).


 ‘With a filter material directly from nature, and by using simple production methods, we believe that our filter paper can become the affordable global water filtration solution and help save lives. Our goal is to develop a filter paper that can remove even the toughest viruses from water as easily as brewing coffee‘, says Albert Mihranyan, Professor of Nanotechnology at Uppsala University (Sweden), who heads the study. Access to safe drinking water is among the UN’s Sustainable Development Goals. More than 748 million people lack access to safe drinking water and basic sanitation. Water-borne infections are among the global causes for mortality, especially in children under age of five, and viruses are among the most notorious water-borne infectious microorganisms. They can be both extremely resistant to disinfection and difficult to remove by filtration due to their small size.

Today we heavily rely on chemical disinfectants, such as chlorine, which may produce toxic by-products depending on water quality. Filtration is a very effective, robust, energy-efficient, and inert method of producing drinking water as it physically removes the microorganisms from water rather than inactivates them. But the high price of efficient filters is limiting their use today.

Safe drinking water is a problem not only in the low-income countries. Massive viral outbreaks have also occurred in Europe in the past, including Sweden’, continues Mihranyan referring to the massive viral outbreak in Lilla Edet municipality in Sweden in 2008, when more than 2400 people or almost 20% of the local population got infected with Norovirus due to poor water.  Small size viruses have been much harder to get rid of, as they are extremely resistant to physical and chemical inactivation.


How To Monitor and Combat Diabetes With A Simple Patch

In the future, diabetics may be able to replace finger prick tests and injections with this non-invasive smart patch to keep their glucose levels in check.


The device is a type of patch which enables diabetic patients to monitor blood sugar levels via sweat without taking blood samples and control glucose levels by injecting medication“, says Kim Dae-Hyeong, researcher at the Institute for Basic Science (IBS), Seoul National University, South Korea.

After analyzing the patient’s sweat to sense glucose, the patch’s embedded sensors constantly test pH, humidity, and temperature – important factors for accurate blood sugar readings. The graphene-based patch is studded with micro-needles coated with medication that pierce the skin painlessly. When the patch senses above normal glucose levels a tiny heating element switches on which dissolves the medication coating the microneedles and releases it into the body. The prototype worked well in mice trials.

Diabetic patients can easily use our device because it does not cause any pain or stress them out. So they can monitor and manage blood glucose levels more often to prevent increasing it. Therefore, our device can greatly contribute to helping patients avoid complications of the disease“, comments Professor Kim Dae-Hyeong. Researchers want to lower the cost of production, while figuring out how to delivery enough medication to effectively treat humans, both major hurdles towards commercialization. The research was published in the journal Nature Nanotechnology in March.


How To Remove All Nanomaterials From Water

Nano implies small—and that’s great for use in medical devices, beauty products and smartphones—but it’s also a problem. The tiny nanoparticles, nanowires, nanotubes and other nanomaterials that make up our technology eventually find their way into water. The Environmental Protection Agency says more 1,300 commercial products use some kind of nanomaterial. And we just don’t know the full impact on health and the environment.

Michigan Technological

Look at plastic,” says Yoke Khin Yap, a professor of physics at Michigan Technological University. “These materials changed the world over the past decades—but can we clean up all the plastic in the ocean? We struggle to clean up meter-scale plastics, so what happens when we need to clean on the nano-scale?”

That challenge is the focus of a new study co-authored by Yap, recently published in the American Chemical Society’s journal Applied Materials and Interfaces. Yap and his team found a novel—and very simple—way to remove nearly 100 percent of nanomaterials from water.


How To Soak Up Oil Spills

In hopes of limiting the disastrous environmental effects of massive oil spills, Materials scientists from Drexel University and Deakin University, in Australia, have teamed up to manufacture and test a new material, called a boron nitride nanosheet, that can absorb up to 33 times its weight in oils and organic solvents—a trait that could make it an important technology for quickly mitigating these costly accidents.

The material, which literally absorbs the oil like a sponge, is the result of support from the Australian Research Council and is now ready to be tested by industry after two years of refinement in the laboratory at Deakin’s Institute for Frontier Materials (IFM).

Alfred Deakin Professor Ying (Ian) Chen, PhD, the lead author of a paper, recently published in Nature Communications, said the material is the most exciting advancement in oil spill remediation technology in decades.

nanopores to soak up oil spillsThe pores found in boron nitride nanosheets allow them to absorb more than 33 times its weight in oil and organic solvents

Oil spills are a global problem and wreak havoc on our aquatic ecosystems, not to mention cost billions of dollars in damage,” Chen said. “Everyone remembers the Gulf Coast disaster, but here in Australia they are a regular problem, and not just in our waters. Oil spills from trucks and other vehicles can close freeways for an entire day, again amounting to large economic losses,” he added.


Green: How To Clean Oil Sands Water Waste

Researchers have developed a process to remove contaminants from oil sands wastewater using only sunlight and nanoparticles that is more effective and inexpensive than conventional treatment methods.

Frank Gu, a professor in the Faculty of Engineering at the University of Waterloo and Canada Research Chair in Nanotechnology Engineering, is the senior researcher on the team that was the first to find that photocatalysis — a chemical reaction that involves the absorption of light by nanoparticles — can completely eliminate naphthenic acids in oil sands wastewater, and within hours. Naphthenic acids pose a threat to ecology and human health. Water in tailing ponds left to biodegrade naturally in the environment still contains these contaminants decades later.

oil sands pond

With about a billion tonnes of water stored in ponds in Alberta, removing naphthenic acids is one of the largest environmental challenges in Canada,” said Tim Leshuk, a PhD candidate in chemical engineering at Waterloo and the leader of the study . “Conventional treatments people have tried either haven’t worked, or if they have worked, they’ve been far too impractical or expensive to solve the size of the problem.  Waterloo’s technology is the first step of what looks like a very practical and green treatment method.


Water To Drink From The Sea

University of Illinois (U. of I.) engineers have found an energy-efficient material for removing salt from seawater that could provide a rebuttal to poet Samuel Taylor Coleridge’s lament, “Water, water, every where, nor any drop to drink.” The material, a nanometer-thick sheet of molybdenum disulfide (MoS2) riddled with tiny holes called nanopores, is specially designed to let high volumes of water through but keep salt and other contaminates out, a process called desalination. In a study published in the journal Nature Communications, the Illinois team modeled various thin-film membranes and found that MoS2 showed the greatest efficiency, filtering through up to 70 percent more water than graphene membranes.


Even though we have a lot of water on this planet, there is very little that is drinkable,” said study leader Narayana Aluru, a U. of I. professor ofmechanical science and engineering. “If we could find a low-cost, efficient way to purify sea water, we would be making good strides in solving the water crisis”.
Finding materials for efficient desalination has been a big issue, and I think this work lays the foundation for next-generation materials. These materials are efficient in terms of energy usage and fouling, which are issues that have plagued desalination technology for a long time,” said Aluru, who also is affiliated with the Beckman Institute for Advanced Science and Technology at the U. of I.

Most available desalination technologies rely on a process called reverse osmosis to push seawater through a thin plastic membrane to make fresh water. “Reverse osmosis is a very expensive process,” Aluru said. “It’s very energy intensive. A lot of power is required to do this process, and it’s not very efficient. In addition, the membranes fail because of clogging. So we’d like to make it cheaper and make the membranes more efficient so they don’t fail as often. We also don’t want to have to use a lot of pressure to get a high flow rate of water.


“Nanopore” Scanners To Find Early Signs Of Cancer

Using tiny “nanopore” scanners that can detect individual DNA molecules, Professor Amit Meller and colleagues are on the hunt for biological markers in cancer cells tha t may help clinicians diagnose colorectal and lung cancers at their earliest stages. Prof. Meller, of the Faculty of Biomedical Engineering at the Technion-Israel Institute of Technology, leads a research group that is a partner in BeyondSeq, an international research consortium looking for new methods of decoding genetic and epigenetic information from medical samples. BeyondSeq, supported by a €6 million grant from Horizon 2020, the European Union’s framework program, was one of only eight consortia chosen out of 450 submitted proposals.


We are the only lab in the consortium working on early diagnosis of cancer biomarkers, which…will allow doctors to combat the cancers much more effectively and save human lives,” Meller explained. “Currently there are no good ways to diagnose colorectal cancer and lung cancer at early stages. Usually these cancers are diagnosed at later stage (stage 2 or above) in which the patients may already have multiple secondary tumors, hence highly complicating treatment.


How To Stay Dry Underwater For Months

Imagine staying dry underwater for months. Now Northwestern University engineers have examined a wide variety of surfaces that can do just that — and, better yet, they know why. The research team is the first to identify the ideal “roughness” needed in the texture of a surface to keep it dry for a long period of time when submerged in water. The valleys in the surface roughness typically need to be less than one micron in width, the researchers found. That’s really small — less than one millionth of a meter — but these nanoscopic valleys have macroscopic impact. Understanding how the surfaces deflect water so well means the valuable feature could be reproduced in other materials on a mass scale, potentially saving billions of dollars in a variety of industries, from antifouling surfaces for shipping to pipe coatings resulting in lower drag. That’s science and engineering, not serendipity, at work for the benefit of the economy.

Dry underwater

The trick is to use rough surfaces of the right chemistry and size to promote vapor formation, which we can use to our advantage,” said Neelesh A. Patankar, a professor of mechanical engineering in the McCormick School of Engineering and Applied Science, who led the research. “When the valleys are less than one micron wide, pockets of water vapor or gas accumulate in them by underwater evaporation or effervescence, just like a drop of water evaporates without having to boil it. These gas pockets deflect water, keeping the surface dry,” he said.

In a study published today (Aug. 18) by the journal Scientific Reports, Patankar and his co-authors explain and demonstrate the nanoscale mechanics behind the phenomenon of staying dry underwater.


How To Clean Up Cigarette Smoke

The Korea Institute of Science and Technology (KIST) research team has developed a nano-catalyst for air cleaning in a smoking room that removes 100% of acetaldehyde, the first class carcinogen, which accounts for the largest portion of the gaseous substances present in cigarette smoke.

Air Cleaning DeviceFor the performance evaluation test, the research team made an air cleaning equipment prototype using the nano-catalyst filter. The equipment was installed in an actual smoking room in the size of 30 square meters (with processing capacity of 4 CMM). About 80% of cigarette smoke elements were processed and decomposed to water vapor and carbon dioxide, within 30 minutes, and 100% of them within 1 hour. The test condition is based on the processing capacity which could circulate the air inside the entire 30 square meter smoking room once every 15 mns.

The nano-catalyst filter uses a technology that decomposes elements of cigarette smoke using oxygen radical, which is generated by decomposing ozone in the air on the surface of the manganese-oxide-based nano-catalyst filter. An evaluation test with total volatile organic compounds (TVOC), such as acetaldehyde, nicotine and tar, which account for the largest volume of gaseous materials in cigarette smoke, is conducted to evaluate the performance of the newly-developed catalyst. The results show that the new catalyst decomposes over 98% of the aforementioned harmful substances.


How To Read DNA Sequences In One Second

Despite having a diameter tens of thousands of times smaller than a human hair, nanopores could be the next big thing in DNA sequencing. By zipping DNA molecules through these tiny holes, scientists hope to one day read off genetic sequences in the blink of an eye. Now, researchers from Brown University have taken the potential of nanopore technology one step further. They have combined a nanopore with a tiny cage capable of trapping and holding a single DNA strand after it has been pulled through the pore. While caged, biochemical experiments can be performed on the strand, which can then be zipped back through the nanopore to look at how the strand has changed.

Nanopore1How the nanoscale cage works? An electrical field draws a strand of DNA in by the smaller hole, bottom, but the curled DNA cannot exit through the larger hole, top. After experimental procedures, a reversed electrical field draws the DNA strand back out of the lower hole, allowing before and after comparison

We see this as a very interesting enabling technique,” said Derek Stein, associate professor of physics and engineering at Brown, who helped develop the technology with his graduate students. “It allows you for the first time to look at the same molecule before and after any kind of chemical reaction that may have taken place.”

A paper describing the device is published in Nature Communications.


Injectable 3D Vaccine Fights Cancer and HIV

One of the reasons cancer is so deadly is that it can evade attack from the body’s immune system, which allows tumors to flourish and spread. Scientists can try to induce the immune system, known as immunotherapy, to go into attack mode to fight cancer and to build long lasting immune resistance to cancer cells. Now, researchers at the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard’s School of Engineering and Applied Sciences (SEAS) show a non–surgical injection of programmable biomaterial that spontaneously assembles in vivo into a 3D structure could fight and even help prevent cancer and also infectious disease such as HIV. Their findings are reported in Nature Biotechnology.

dentritic cells
A microscope image shows many of the immune system’s dendritic cells that were collected from a 3D scaffold three days after in vivo injection. The 3D scaffold effectively recruits and activates the dendritic cells to trigger an immune response against specific cells, such as cancerous cells

We can create 3D structures using minimally–invasive delivery to enrich and activate a host’s immune cells to target and attack harmful cells in vivo,” said the study’s senior author David Mooney, Ph.D., who is a Wyss Institute Core Faculty member and the Robert P. Pinkas Professor of Bioengineering at Harvard SEAS. “Nano–sized mesoporous silica particles have already been established as useful for manipulating individual cells from the inside, but this is the first time that larger particles, in the micron–sized range, are used to create a 3D in vivo scaffold that can recruit and attract tens of millions of immune cells,” said co-lead author Jaeyun Kim, Ph.D., an Assistant Professor of Chemical Engineering at Sungkyunkwan University (Korea) and a former Wyss Institute Postdoctoral Fellow.

Graphene soaks up Carbon, Cause of Global Warming

Chemists and engineers at Oregon State University (OSU) have discovered a fascinating new way to take some of the atmospheric carbon dioxide that’s causing the greenhouse effect and use it to make an advanced, high-value material for use in energy storage products.This innovation in nanotechnology won’t soak up enough carbon to solve global warming, researchers say. However, it will provide an environmentally friendly, low-cost way to make nanoporous graphene for use in “supercapacitors” – devices that can store energy and release it rapidly. Such devices are used in everything from heavy industry to consumer electronics.

greenhouse gas2
There are other ways to fabricate nanoporous graphene, but this approach is faster, has little environmental impact and costs less,” said Xiulei (David) Ji, an OSU assistant professor of chemistry in the OSU College of Science and lead author on the study. “The product exhibits high surface area, great conductivity and, most importantly, it has a fairly high density that is comparable to the commercial activated carbons. “And the carbon source is carbon dioxide, which is a sustainable resource, to say the least,” Ji said. “This methodology uses abundant carbon dioxide while making energy storage products of significant value.”

The findings were just published in Nano Energy by scientists from the OSU College of Science, OSU College of Engineering, Argonne National Laboratory, the University of South Florida and the National Energy Technology Laboratory in Albany, Ore. The work was supported by OSU.