Graphene possesses strong bacteria-killing properties, making it a potential breakthrough in the battle against antibiotic-resistant bacteria. Until now, there have been no effective means to harness these properties, limiting its use in healthcare. Researchers at Chalmers University of Technology in Sweden have now addressed this issue by employing technology similar to that found in standard fridge magnets. The outcome is a super-thin, acupuncture-like coating that can be applied to catheters and implants, capable of eliminating 99.9% of bacteria on any surface.
Infections linked to healthcare are a widespread challenge globally, resulting in considerable suffering, soaring healthcare expenses, and an increased risk of antibiotic resistance. Most of these infections arise from medical devices like catheters, hip and knee implants, and dental devices, where bacteria can infiltrate the body through foreign surfaces. At Chalmers University of Technology, researchers have investigated how graphene, an atomically thin two-dimensional form of graphite, can aid in combating antibiotic resistance and healthcare-related infections. The research team has previously demonstrated that vertically oriented graphene flakes can prevent bacterial attachment to surfaces; instead, the bacteria are effectively destroyed by the sharp edges of the flakes.
“We are developing a graphene-based, ultra-thin, antibacterial material that can be coated onto any surface, including biomedical devices, surgical surfaces, and implants, to prevent bacterial adherence. Since graphene physically inhibits bacterial attachment, it offers the advantage of not promoting antibiotic resistance, unlike traditional chemical alternatives such as antibiotics,” explains Ivan Mijakovic, Professor of Systems Biology at Chalmers University of Technology and co-author of the recently published study.
Kills 99.9% of bacteria on a surface
However, the research team has encountered a significant challenge. Even though laboratory tests have confirmed the bactericidal properties of graphene, the researchers struggled to manage the orientation of the graphene flakes in a way that could be applied to the surfaces of medical devices. Up until now, they could only control the direction of the flakes in one specific manner determined by the manufacturing process. Fortunately, the team believes they have achieved a major breakthrough that enhances practical applications in healthcare and beyond.
“We have discovered a method to control the effect of graphene in multiple directions with a high degree of uniformity. This new orientation technique enables the integration of graphene nanoplates into medical plastic surfaces, resulting in an antibacterial coating that kills 99.9% of any bacteria that attempt to adhere. This opens the door for improved flexibility in manufacturing bacteria-killing medical devices utilizing graphene,” states Roland Kádár, Professor of Rheology at Chalmers University of Technology.
Unprecedented efficiency through magnetic field control
By strategically arranging earth magnets in a circular formation to create a linear magnetic field, the researchers achieved a uniform orientation of graphene, yielding an impressive bactericidal effect on surfaces of various shapes.
The methodology, detailed in Advanced Functional Materials, is referred to as the “Halbach array.” This technique reinforces and normalizes the magnetic field within the array while diminishing it on the opposite side, allowing graphene to align uniformly. The technology is akin to that seen in typical fridge magnets.
“This is the first use of the Halbach array technique to orient graphene in a polymer nanocomposite. Given our results, we are eager to implement these graphene-coated solutions in the healthcare sector to lower the incidence of healthcare-related infections, reduce patient suffering, and combat antibiotic resistance,” says Viney Ghai, a researcher in Rheology and Soft Matter Processing at Chalmers University of Technology.
The new orientation technology holds substantial promise in various other fields, including batteries, supercapacitors, sensors, and durable, water-resistant packaging materials.
“Considering its wide-ranging potential, this approach truly opens new avenues in material alignment, offering a potent tool for the effective design and customization of nanostructures that emulate the complex structures found in nature,” adds Roland Kádár.
