Category: Nanotechnology

Are graphene-coated face masks a COVID-19 miracle – or another health risk?

Officials in Quebec, Canada recently removed graphene-coated face masks from schools and daycare centers. Ridofranz/iStock via Getty Images

by C. Michael White (University of Connecticut)

As a COVID-19 and medical device researcher, I understand the importance of face masks to prevent the spread of the coronavirus. So I am intrigued that some mask manufacturers have begun adding graphene coatings to their face masks to inactivate the virus. Many viruses, fungi and bacteria are incapacitated by graphene in laboratory studies, including feline coronavirus.

Because SARS CoV-2, the coronavirus that causes COVID-19, can survive on the outer surface of a face mask for days, people who touch the mask and then rub their eyes, nose, or mouth may risk getting COVID-19. So these manufacturers seem to be reasoning that graphene coatings on their reusable and disposable face masks will add some anti-virus protection. But in March, the Quebec provincial government removed these masks from schools and daycare centers after Health Canada, Canada’s national public health agency, warned that inhaling the graphene could lead to asbestos-like lung damage.

Is this move warranted by the facts, or an over-reaction? To answer that question, it can help to know more about what graphene is, how it kills microbes, including the SARS-COV-2 virus, and what scientists know so far about the potential health impacts of breathing in graphene.

Hand wearing blue vinyl protective glove holding a small tube.
Batch samples of nano-scale graphene material at a graphene processing factory. Monty Rakusen/Getty Images

How does graphene damage viruses, bacteria and human cells?

Graphene is a thin but strong and conductive two-dimensional sheet of carbon atoms. There are three ways that it can help prevent the spread of microbes:

– Microscopic graphene particles have sharp edges that mechanically damage viruses and cells as they pass by them.

– Graphene is negatively charged with highly mobile electrons that electrostaticly trap and inactivate some viruses and cells.

– Graphene causes cells to generate oxygen free radicals that can damage them and impairs their cellular metabolism.

Dr. Joe Schwarcz at McGill University explains graphene

Why graphene may be linked to lung injury

Researchers have been studying the potential negative impacts of inhaling microscopic graphene on mammals. In one 2016 experiment, mice with graphene placed in their lungs experienced localized lung tissue damage, inflammation, formation of granulomas (where the body tries to wall off the graphene), and persistent lung injury, similar to what occurs when humans inhale asbestos. A different study from 2013 found that when human cells were bound to graphene, the cells were damaged.

In order to mimic human lungs, scientists have developed biological models designed to simulate the impact of high concentration aerosolized graphene – graphene in the form of a fine spray or suspension in air – on industrial workers. One such study published in March 2020 found that a lifetime of industrial exposure to graphene induced inflammation and weakened the simulated lungs’ protective barrier.

It’s important to note that these models are not perfect options for studying the dramatically lower levels of graphene inhaled from a face mask, but researchers have used them in the past to learn more about these sorts of exposures. A study from 2016 found that a small portion of aerosolized graphene nanoparticles could move down a simulated mouth and nose passages and penetrate into the lungs. A 2018 study found that brief exposure to a lower amount of aerosolized graphene did not notably damage lung cells in a model.

From my perspective as a researcher, this trio of findings suggest that a little bit of graphene in the lungs is likely OK, but a lot is dangerous.

Although it might seem obvious to compare inhaling graphene to the well-known harms of breathing in asbestos, the two substances behave differently in one key way. The body’s natural system for disposing of foreign particles cannot remove asbestos, which is why long-term exposure to asbestos can lead to the cancer mesothelioma. But in studies using mouse models to measure the impact of high dose lung exposure to graphene, the body’s natural disposal system does remove the graphene, although it occurs very slowly over 30 to 90 days.

The findings of these studies shed light on the possible health impacts of breathing in microscopic graphene in either small or large doses. However, these models don’t reflect the full complexity of human experiences. So the strength of the evidence about either the benefit of wearing a graphene mask, or the harm of inhaling microscopic graphene as a result of wearing it, is very weak.

No obvious benefit but theoretical risk

Graphene is an intriguing scientific advance that may speed up the demise of COVID-19 virus particles on a face mask. In exchange for this unknown level of added protection, there is a theoretical risk that breathing through a graphene-coated mask will liberate graphene particles that make it through the other filter layers on the mask and penetrate into the lung. If inhaled, the body may not remove these particles rapidly enough to prevent lung damage.

The health department in Quebec is erring on the side of caution. Children are at very low risk of COVID-19 mortality or hospitalization, although they may infect others, so the theoretical risk from graphene exposure is too great. However, adults at high immediate risk of harm from contracting COVID-19 may choose to accept a small theoretical risk of long-term lung damage from graphene in exchange for these potential benefits.

C. Michael White, Distinguished Professor and Head of the Department of Pharmacy Practice, University of Connecticut

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Newly discovered material may ease wear and tear on extraterrestrial vehicles

Read the full story from Missouri S&T.

As NASA’s Mars Perseverance Rover continues to explore the surface of Mars, scientists on Earth have developed a new nanoscale metal carbide that could act as a “superlubricant” to reduce wear and tear on future rovers.

Researchers in Missouri S&T’s chemistry department and Argonne National Laboratory’s Center for Nanoscale Materials, working with a class of two-dimensional nanomaterials known as MXenes, have discovered that the materials work well to reduce friction. The materials also should perform better than conventional oil-based lubricants in extreme environments, says Dr. Vadym Mochalin, associate professor of chemistry at Missouri S&T, who is leading the research.

Adapting solar energy technology to detect chemical warfare agents and pesticides

Read the full story from the ARC Centre of Excellence in Exciton Science.

In a colorful solution to a dangerous problem, Australian scientists are adapting a component from cutting-edge solar cells to design a rapid, light-based detection system for deadly toxins.

How Does Nanotechnology Address Problems in the Environment?

Read the full story at Azo Nano.

Environmental protection is one of the critical challenges faced by the human race. Over the years, we have unintentionally devastated our surroundings by creating and discarding plastics, contributed to climate change by mining and burning fossil fuels, and polluted our air and waterways with human-made creations.

But now it is time to repair the environment and our relationship with it, with nanotechnology set to play a vital role in securing the future sustainability of our planet.

Flexible and reusable carbon nano-fibre membranes for airborne contaminants capture

Al-Attabi, R. et al (2021). “Flexible and reusable carbon nano-fibre membranes for airborne contaminants capture.” Science of the Total Environment 754, 142231. https://doi.org/10.1016/j.scitotenv.2020.142231

Abstract: Airborne aerosol pollutants generated from combustion vehicles exhausts, industrial facilities and microorganisms represent serious health challenges. Although membrane separation has emerged as a technique of choice for airborne contaminants removal, allowing for both size exclusion and surface adsorption. Here, electrospun carbon nanofibre mats were formed from poly(acrylonitrile) by systematic stabilization and carbonization processes to generate flexible and self-standing membranes for air filtration. The great mechanical flexibility of the electrospun carbon-nanofibre membranes was achieved through extreme quenching conditions on a carbon fibre processing line, allowing for complete carbonization in just 3 min. The carbonized nanofibre membranes, with fibre diameters in the range of 218 to 565 nm exhibited modulus of elasticity around 277.5 MPa. The samples exhibited air filtration efficiencies in the range of 97.2 to 99.4% for aerosol particle in the size of 300 nm based on face velocity, higher than benchmark commercial glass fibre (GF) air filters. The carbonized electrospun nanofibre membranes also yielded excellent thermal stability withstanding temperatures up to 450 °C, thus supporting the development of autoclavable and recyclable membranes. This significant and scalable strategy provides opportunities to mass-produce reusable air filters suitable for otherwise complex airborne pollutants, including volatile organic carbons and bio-contaminants, such as viruses.

Nanocrystals from recycled wood waste make carbon-fiber composites tougher

Read the full story from Texas A&M University.

Researchers have used a natural plant product, called cellulose nanocrystals, to pin and coat carbon nanotubes uniformly onto the carbon-fiber composites. The researchers said their prescribed method is quicker than conventional methods and also allows the designing of carbon-fiber composites from the nanoscale.

Associated journal article: Shadi Shariatnia, Annuatha V. Kumar, Ozge Kaynan, Amir Asadi. Hybrid Cellulose Nanocrystal-Bonded Carbon Nanotubes/Carbon Fiber Polymer Composites for Structural ApplicationsACS Applied Nano Materials, 2020; 3 (6): 5421 DOI: 10.1021/acsanm.0c00785

NSF awards $20M to Center for Sustainable Nanotechnology

Read the full story from the University of Minnesota.

University of Minnesota Twin Cities researchers announced today that they are part of a team of researchers from the National Science Foundation (NSF) Center for Sustainable Nanotechnology who have received a five-year, $20 million grant from the NSF Division of Chemistry.

The grant will allow continued research on evaluating the molecular-level impact of nanotechnology on the environment and living things. The center was initially funded in 2012.

Fish scales could make wearable electronics more sustainable

Read the full story from the American Chemical Society.

Flexible temporary electronic displays may one day make it possible to sport a glowing tattoo or check a reading, like that of a stopwatch, directly on the skin. In its current form, however, this technology generally depends on plastic. New research in ACS Nano describes a way to make these displays, which would likely be discarded after a single use, more environmentally friendly using a plentiful and biodegradable resource: fish scales.

40% of food in America ends up in the trash. Is nanopackaging the answer?

Read the full story at Massive Science.

Consumer habits aren’t enough to curb the impacts of food waste — packaging companies have the opportunity to make a big difference

Nanoparticles may have bigger impact on the environment than previously thought

Read the full story from the University of Minnesota.

In a first-of-its-kind study, researchers have shown that nanoparticles may have a bigger impact on the environment than previously thought.

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