Graphene can kill bacteria on surgical implants: study
A tiny layer of graphene flakes can act as a deadly weapon against bacteria, and stop infections during procedures such as implant surgery, according to researchers, including one of Indian-origin.
Operations for surgical implants, such as hip and knee replacements or dental implants, have increased in recent years, said researchers at Chalmers University of Technology in Sweden.
However, in such procedures, there is always a risk of bacterial infection. In the worst case scenario, this can cause the implant to not attach to the skeleton, meaning it must be removed, they said.
“We want to prevent bacteria from creating an infection. Otherwise, you may need antibiotics, which could disrupt the balance of normal bacteria and also enhance the risk of antimicrobial resistance by pathogens,” said Santosh Pandit, postdoc at Chalmers University. Bacteria travel around in fluids, such as blood, looking for a surface to cling on to. Once in place, they start to grow and propagate, forming a protective layer, known as a biofilm.
In the study published in the journal Advanced Materials Interfaces, researchers have shown that a layer of vertical graphene flakes forms a protective surface that makes it impossible for bacteria to attach. Instead, bacteria are sliced apart by the sharp graphene flakes and killed. Coating implants with a layer of graphene flakes can therefore help protect the patient against infection, eliminate the need for antibiotic treatment, and reduce the risk of implant rejection.
The osseointegration — the process by which the bone structure grow to attach the implant — is not disturbed. In fact, the graphene has been shown to benefit the bone cells. The sharp flakes do not damage human cells. The reason is simple: one bacterium is one micrometer — one thousandth of a millimetre – in diameter, while a human cell is 25 micrometers. “Graphene has high potential for health applications. But more research is needed before we can claim it is entirely safe. Among other things, we know that graphene does not degrade easily,” said Jie Sun, an associate professor at Chalmers University. Good bacteria are also killed by the graphene. But that is not a problem, as the effect is localised and the balance of microflora in the body remains undisturbed, researchers said.