Copolymer could keep catheters bacteria-free

Urinary tract catheters are widely used in hospitalized patients, but they often lead to bacterial infections. Researchers have now developed a biocompatible copolymer that could prevent bacteria from colonizing catheters and spreading into patients (Sci. Adv. 2023, DOI: 10.1126/sciadv.add7474).

Catheters coated with antibacterial silver have previously produced disappointing results, says Andrew L. Hook, a biomaterials researcher at the University of Nottingham, and catheter-associated urinary tract infections are responsible for about $1.7 billion in annual medical costs in the US alone.

After screening about 400 acrylate polymers, Hook and his colleagues found that poly(tert-butylcyclohexyl acrylate) stopped common bacteria from forming biofilms and prevented a buildup of biomineral crystals that can block catheters. Meanwhile, poly(2-hydroxy-3-phenoxypropyl acrylate) inhibited the swarming behavior that allows some bacteria to spread along the catheter to infect patients.

The researchers united these two polymers into a copolymer, fine-tuning the proportions to maximize their combined effects. The copolymer also reduced the accumulation of fibrinogen, an inflammation-response protein produced by patients that can help bacteria stick to catheter surfaces.

Overall, the copolymer offered a 15-fold reduction in biofilm formation, compared with the silicone typically used in catheters. “To the best of our knowledge, this is the first material that can prevent swarming, and biofilm formation, and biomineralization,” Hook says. The inexpensive copolymer could be coated onto silicone catheters, and the team now plans to test the material in vivo.