Graphene spike mat and fridge magnet technology to combat antibiotic resistance

Graphene has the potential to play a crucial role in the fight against antibiotic-resistant bacteria due to its strong bactericidal properties. Until now, there have been no effective ways to control these properties – and thus no way to harness graphene's potential in healthcare. Researchers at Chalmers University of Technology in Sweden have now solved the problem by using the same technology used in an ordinary refrigerator magnet. The result is an ultra-thin, acupuncture-like surface that can be used as a coating on catheters and implants – and kills 99.99 percent of all bacteria on a surface.

Healthcare-related infections are a widespread problem worldwide. They cause great suffering, high healthcare costs and increase the risk of increasing antibiotic resistance. Most infections occur in connection with the use of various medical devices such as catheters, hip prostheses, knee prostheses and dental implants, where bacteria can enter the body via a foreign surface. At Chalmers University of Technology, researchers have investigated how graphene, an atomically thin two-dimensional graphite material, can help combat antibiotic resistance and infections in healthcare. The research team was previously able to show how vertically standing graphene flakes prevent bacteria from attaching to the substrate. Instead, the bacteria are cut into pieces by the razor-sharp flakes and die.

“We are developing an ultra-thin, antibacterial graphene-based material that can be applied to any surface, including biomedical devices, surgical surfaces and implants. To Exclude bacteria. Since graphene prevents bacteria from physically attaching to a surface, it has the added advantage of not running the risk of increasing antibiotic resistance, unlike other chemical alternatives such as antibiotics,” says Ivan Mijakovic, Professor of Systems Biology at Chalmers University of Technology and one of the authors of the recently published study.

Kills 99.99% of all bacteria on a surface

However, the researchers faced a challenge. Although the bactericidal properties could be demonstrated in the laboratory, the researchers were not yet able to control the orientation direction of the graphene flakes – and therefore could not apply the material to surfaces of medical devices in healthcare. Until now, the bactericidal properties of graphene could only be controlled in one specific direction: the flow direction of the manufacturing process. But now the Chalmers researchers have achieved a promising breakthrough for a practical application in healthcare – and beyond.

“We have managed to find a way to practically control the action of graphene in several different directions and with a very high degree of uniformity of alignment. This new alignment method makes it possible to integrate graphene nanoplates into medical plastic surfaces and obtain an antibacterial surface that kills 99.99% of bacteria that try to attach. This paves the way for significantly more flexibility in the production of bacteria-killing medical devices using graphene,” says Roland Kádár, Professor of Rheology at Chalmers University of Technology.

Unprecedented efficiency through control of magnetic fields

By arranging the earth's magnets in a circular manner, which causes the magnetic field within the arrangement to run in a straight direction, the researchers were able to achieve a uniform alignment of the graphene and a very high bactericidal effect on surfaces of any shape.

The method, published in Advanced functional materials, is called “Halbach array” and means that the magnetic field inside the magnet array is strengthened and uniform, while on the other side it is weakened, allowing for a strong unidirectional alignment of the graphene. The technology is similar to that of a refrigerator magnet.

“This is the first time that the Halbach array method has been used to align graphene in a polymer nanocomposite. Now that we have seen the results, we naturally want to introduce these graphene sheets into the healthcare sector so that we can reduce the number of infections occurring in healthcare settings, alleviate patient suffering and counteract antibiotic resistance,” says Viney Ghai, researcher in rheology and soft matter processing at Chalmers University of Technology.

The new alignment technology has significant potential in other areas, such as batteries, supercapacitors, sensors and durable waterproof packaging materials.

“Given its far-reaching implications in these fields, this method truly opens up new horizons in material orientation and provides a powerful tool for the successful design and tailoring of nanostructures that mimic the complex architectures of natural systems,” says Roland Kádár..

Caption: Illustration of how the razor-sharp graphene flakes can line up on a surface and kill bacteria without harming healthy human cells. The bactericidal graphene surfaces developed at Chalmers University of Technology could soon be used in medical devices thanks to a brand-new method that uses refrigerator magnet technology to control the bactericidal effect of graphene.

Photo credit: Yen Sandqvist

More about research:

Read the study: Achieving arbitrarily uniform alignment of nanostructures in magnetic fields over long distances

The study was conducted within the 2D-Tech competence center at Chalmers University of Technology. The center is funded by Vinnova, Chalmers and 19 industrial partners and is a Swedish center for research and innovation in 2D material-based technology for industrial applications.

For further information please contact:

Roland Kádár, Professor of Rheology at the Faculty of Industrial and Materials Science, Chalmers University of Technology
[email protected]
+46-31-772 12 56

Viney Ghai, researcher in rheology and soft matter processing at the Department of Industrial and Materials Science at Chalmers University of Technology
[email protected]

Ivan Mijakovic, Professor of Systems Biology at the Faculty of Life Sciences, Chalmers University of Technology
[email protected]

Roland Kádár speaks English and Viney Ghai speaks English, Hindi and Punjabi. Both are available for live and recorded interviews. Chalmers has podcast radio studios and film equipment that can be used for TV, radio or podcast enquiries.

More about the method:

In laboratory experiments, the researchers exposed various bacterial cultures to graphene surfaces whose magnetic fields had been manipulated using the new method. To calculate how effective the method was, bacterial survival was measured using the CFU (colony forming unit), a measure that measures the number of microorganisms in a bacterial colony. Using scanning electron microscopy (SEM), the researchers were also able to scan bacterial colonies to visualize and confirm the physical disruption of the graphene on the bacterial cells.

Additional accompanying material – film:

Watch the film to learn how a tiny layer of graphene flakes becomes a deadly weapon, killing bacteria and preventing infections during procedures such as implant surgery:

Emma FryPress Officer+46 31 772 50 [email protected]

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