(Press-News.org) When old food packaging, discarded children’s toys and other mismanaged plastic waste break down into microplastics, they become even harder to clean up from oceans and waterways. These tiny bits of plastic also attract bacteria, including those that cause disease. In a study in ACS Nano, researchers describe swarms of microscale robots (microrobots) that captured bits of plastic and bacteria from water. Afterward, the bots were decontaminated and reused. Watch a video of them swarming.
The size of microplastics, which measure 5 millimeters or less, adds another dimension to the plastic pollution problem because animals can eat them, potentially being harmed or passing the particles into the food chain that ends with humans. So far, the health effects for people are not fully understood. However, microplastics themselves aren’t the only concern. These pieces attract bacteria, including pathogens, which can also be ingested. To remove microbes and plastic from water simultaneously, Martin Pumera and colleagues turned to microscale robotic systems, comprised of many small components that work collaboratively, mimicking natural swarms, like schools of fish.
To construct the bots, the team linked strands of a positively charged polymer to magnetic microparticles, which only move when exposed to a magnetic field. The polymer strands, which radiate from the surface of the beads, attract both plastics and microbes. And the finished products — the individual robots — measured 2.8 micrometers in diameter. When exposed to a rotating magnetic field, the robots swarmed together. By adjusting the number of robots that self-organized into flat clusters, the researchers found that they could alter the swarm’s movement and speed.
In lab experiments, the team replicated microplastics and bacteria in the environment by adding fluorescent polystyrene beads (1 micrometer-wide) and actively swimming Pseudomonas aeruginosa bacteria, which can cause pneumonia and other infections, to a water tank. Next, the researchers added microrobots to the tank and exposed them to a rotating magnetic field for 30 minutes, switching it on and off every 10 seconds. A robot concentration of 7.5 milligrams per milliliter, the densest of four concentrations tested, captured approximately 80% of the bacteria. Meanwhile, at this same concentration, the number of free plastic beads also gradually dropped, as they were drawn to the microrobots. Afterward, the researchers collected the robots with a permanent magnet and used ultrasound to detach the bacteria clinging to them. They then exposed the removed microbes to ultraviolet radiation, completing the disinfection. When reused, the decontaminated robots still picked up plastic and microbes, albeit smaller amounts of both. This microrobotic system provides a promising approach for ridding water of plastic and bacteria, the researchers note.
The authors acknowledge funding from the European Regional Development Fund/Europeal Social Fund project TECHSCALE, the REFRESH program of the European Union and CzechNanoLab.
The paper’s abstract will be available on May 8 at 8 a.m. Eastern time here: http://pubs.acs.org/doi/abs/10.1021/acsnano.4c02115
###
The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS’ mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and all its people. The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a leader in scientific information solutions, its CAS division partners with global innovators to accelerate breakthroughs by curating, connecting and analyzing the world’s scientific knowledge. ACS’ main offices are in Washington, D.C., and Columbus, Ohio.
To automatically receive news releases from the American Chemical Society, contact newsroom@acs.org.
Note: ACS does not conduct research, but publishes and publicizes peer-reviewed scientific studies.
Follow us: X, formerly Twitter | Facebook | LinkedIn | Instagram
END
How do city residents feel about animals in their immediate surroundings? A recent study by the Technical University of Munich (TUM), the University of Jena and the Vienna University of Technology shows how different the acceptance of various wild animals in urban areas is. Important factors are the places where the animals are found and their level of popularity - squirrels and ladybugs come out on top here. The results have important implications for urban planning and nature conservation.
The relationship between city inhabitants and urban animals is complex, ...
PULLMAN, Wash. – When breastfeeding mothers in a recent study used cannabis, its psychoactive component THC showed up in the milk they produced. The Washington State University-led research also found that, unlike alcohol, when THC was detected in milk there was no consistent time when its concentration peaked and started to decline.
Importantly, the researchers discovered that the amount of THC they detected in milk was low – they estimated that infants received an average of 0.07 mg of THC per day. For comparison, a common low-dose edible contains 2 mg of THC. The research team stressed that it is unknown whether this amount has any impact ...
Chemistry, with its intricate processes and vast potential for innovation, has always been a challenge for automation. Traditional computational tools, despite their advanced capabilities, often remain underutilized due to their complexity and the specialized knowledge required to operate them.
Now, researchers with the group of Philippe Schwaller at EPFL, have developed ChemCrow, an AI that integrates 18 expertly designed tools, enabling it to navigate and perform tasks within chemical research with unprecedented efficiency. “You might wonder why a crow?” asks Schwaller. “Because ...
An international team led by researchers at the University of Toronto has found a family of natural compounds with potential as new and more effective treatments for parasitic worms. The compounds stall the unique metabolic process that worms use to survive in the human gut.
Parasitic worms transmitted through soil wreak havoc in developing countries in the tropics. Infection by these parasites leads to malaise, weakness, malnutrition and other debilitating symptoms, and can cause developmental defects in children and impair their growth.
“Soil-transmitted parasitic worms infect over one billion people around the world, typically in low-income communities of developing countries ...
Freshwater resources are limited, accounting for only 3.5% of Earth’s water, with just 0.25% accessible on the surface. Nevertheless, freshwater lakes are essential for ecosystem functioning and global carbon cycling due to their high biological productivity and microbial activity. They are critical to human survival, providing drinking water, supporting agriculture, fisheries, and recreation. However, climate change – particularly rising temperatures – threatens these habitats by disrupting microbial communities that are essential for nutrient cycling and water quality maintenance.
Challenging established evolutionary paradigms
“Considering ...
A gene previously linked to intellectual disability has been found to regulate learning and memory in mice.
The gene, called KDM5B has previously been linked to some intellectual disability disorders and autism. In the general population, some variants are also associated with reduced brain function, although not sufficient to cause an overt disability or behavioural symptoms.
Now, researchers at King’s College London, the University of Exeter and the University of California Irvine have found that reduced function of the gene in the brain results in loss of learning ability and memory and a reduction in the brain’s ability to strengthen connections between neurons, ...
COLUMBUS, OHIO – Is the status of “perfect parent” attainable?
Researchers leading a national dialogue about parental burnout from The Ohio State University College of Nursing and the university’s Office of the Chief Wellness Officer say “no,” and a new study finds that pressure to try to be “perfect” leads to unhealthy impacts on both parents and their children.
The survey of more than 700 parents nationwide from June 15 – July 28, 2023 is summarized in the new report, “The Power of Positive Parenting: Evidence to Help Parents and Their Children Thrive.” The data shows that:
Fifty-seven ...
The study was funded by the National Institute for Health and Care Research (NIHR), the research arm of the Department of Health and Social Care (DHSC), and was led by Professor Christina Vogel, Director of the Centre for Food Policy at City, University of London. DHSC commissioned this work to evaluate the Healthy Start scheme in England and understand how the scheme can be improved to reach more eligible families.
The Healthy Start scheme was launched in 2006. It offers financial support and free vitamins for pregnant ...
A new study highlighting the risks encountered by food delivery couriers reveals a majority feel ‘unsafe’ when at work with every woman surveyed having experienced sexual harassment or abuse.
Led by Dr Pedro Mendonca from the Centre for Employment, Work and the Professions (CREWs) at Heriot-Watt University’s Edinburgh Business School, the two-year project gathered feedback from 207 workers, including 33 women, employed in the food delivery industry in cities across Scotland.
It reveals more than 81% felt unsafe in their job yet continued due to financial necessity while 78% believed their ...
URBANA, Ill. – COVID-19 vaccination rates remain low in many African countries, often because providing access to vaccines is difficult in remote areas. A new international research project showed that intervention with mobile vaccination teams in Sierra Leone is an effective way of reaching rural populations to increase vaccination uptake.
Madison Levine, a doctoral student in the Department of Agricultural and Consumer Economics (ACE), part of the College of Agricultural, Consumer and Environmental Sciences (ACES) at the University of Illinois Urbana-Champaign, participated in the project as a field research assistant. She is a co-author ...