Technical University of Denmark: Spinout will stop chronic implant infections

Many people walk around with an artificial implant in their body without giving it a further thought. It could be a dental implant to replace a missing tooth, or a hip implant to replace a damaged hip socket. While implants help when the body fails, they are also associated with a risk.

In the United States alone, 17 million people are hospitalized each year with a chronic infection—of whom at least 550,000 die. Studies show that the high number of chronic infections is related to an increase in the number of patients having an implant procedure.

“What can happen is that the body’s bacteria can settle on the surface of the implant in a layer so thin as to remain undetected by the immune system. This layer develops into a biofilm and means that we are walking around with these implants, which could potentially be small ticking time bombs, without any possibility of reacting before it turns into a chronic infection,” explains Professor Paul Michael Petersen, professor and Head of Section at DTU Fotonik. He believes the problem is one of the most overlooked in the health sector.

Together with Associate Professor Yiyu Ou at DTU Fotonik, he has developed a technological solution that can prevent infections from occurring. Using a special method, the researchers use nanostructures to create a jagged surface on the implant so bacteria cannot stick. Instead, the jagged points ‘puncture’ the bacterial cell membrane causing the bacteria to die.

So far, laboratory tests show that the proportion of bacteria that get stuck is reduced by 90 per cent compared with implants that have a smooth surface.

“I’ve been really surprised at how good our technology is at breaking down the infections. The efficacy and results have far exceeded my expectations,” says Paul Michael Petersen.

Greater durability
The idea of fabricating nanostructures to kill bacteria is not really new in itself. Here, the researchers are up against competitors that are already cooperating with the market’s major medical companies.

However, where their competitors ‘coat’ the surface of the implant with nanostructures, the researchers from DTU Fotonik have developed a method whereby the nanostructures are incorporated into the implant itself.

“We haven’t come across anyone else using this method. With our method the protection remains on all surfaces, even the complicated ones.”
Yiyu Ou, Associate Professor, DTU Fotonik
“Using a patented technology, we insert the structures into the implant itself which is made of titanium. It works just like when you engrave something onto a material,” explains Paul Michael Petersen.

The researchers emphasize that the method protects the implant from infections for more than ten years. In comparison, the competitors’ coating method only lasts for up to five years.

“We haven’t come across anyone else using this method. The integration into the design itself is what is attractive about our invention. With our method the protection remains on all surfaces, even the complicated ones,” says Yiyu Ou.

In 2021, the invention led to the establishment of the spinout company Adina Technologies and today the researchers have a patent on the solution.