Infections from urinary catheters, commonly used for patients suffering from incontinence, affect some 10 million patients. They account for 40 % of all hospital-associated infections and are becoming more difficult to treat due to growing antibiotic resistance. The NANOELAST project is developing a new generation of catheters made from a novel nanomaterial which kills bacteria associated with urinary tract infections. “It is a material with a natural mechanism which enables it to fight off bacteria,” explains project coordinator Anand Kumar Rajasekharan, CEO of Amferia in Sweden, the company developing the antibacterial catheter. The patented nanomaterial was originally developed by Chalmers University of Technology in Gothenburg, Sweden. It is a soft and flexible nanoporous polymer with rubber-like properties, known as an elastomer, which can stretch without breaking. The surface of the nanomaterial has antimicrobial peptides permanently anchored to it. These are small molecules inspired by the human or mammalian immune system that fight off bacteria by penetrating the bacterial cell wall. “It is a material that is very tough and elastic. When the bacteria come into contact with the nanomaterial’s surface, it disrupts the bacterial cell wall, and kills them,” Rajasekharan says. “Different strains of bacteria cause infection, and for catheters there are one or two strains that are important to identify by testing in the laboratory, so we did that work,” he adds.
Turning the novel material into a tube
The bigger problem was to go from the precursor nanomaterial, which is a paste-like substance, and transform it into a tube of a certain dimension as well as producing it in high volumes. “Adapting the material to a tube geometry and maintaining the structure and nanoarchitecture was the challenge we faced throughout the project.” So the team had to test and adjust the process to match the raw material form that they had. The standard industrial process to make tubes is polymer extrusion. “It’s usually designed for liquid melts but we had more of a viscous paste, and putting that through an extruder is challenging so it needed modification,” Rajasekharan explains. It also had to be a process that could be easily adopted by existing manufacturers without huge outlay. Before the project started, the company had discussions with potential partners to identify possible interest in the catheter product. “Our customers would probably be manufacturers of existing catheters who would see this as an add-on to their product line,” he notes.
Scaling up requires the material to be stable
Amferia previously developed wound dressings based on similar antibacterial nanomaterials and has already verified many safety and biocompatibility aspects from preclinical studies. “When it comes to scalability, one of the main things is availability of the raw materials. This is a material that has a certain composition of polymers. We have confirmed that these are non-toxic and fully biocompatible materials and we were able to find suppliers,” Rajasekharan says. To scale up for industrial production, any novel nanomaterial also needs to be stable. “We are presently performing laboratory tests to verify that the shelf life and storage match those of current catheters on the market, usually 1-2 years. Early data has been promising,” he adds. “One of the next steps is to partner with someone with experience of the production and regulatory process as this will help an efficient translation of the technology from our lab to the clinics and eventually, to the patient.”
NANOELAST, catheter, urinary tract, incontinence, nanomaterial, antibiotic resistance, antibacterial, polymers, elastomer