Hospital germs: Antimicrobial curtains
Hospital germs and pathogens are not always transmitted directly from person to person. They can also spread via germ-contaminated objects. Together with the chemical company BASF, the Spiez Laboratory and the Technical University of Berlin, Empa researchers have developed coated textiles that inhibit or even kill pathogens. In future, they could be used as antimicrobial curtains in hospitals.
Patients, visitors and medical staff in hospitals touch surfaces of all kinds countless times a day. These door handles, handrails or elevator buttons can serve as transport vehicles for pathogens such as hospital germs or viruses. Smooth surfaces are comparatively easy to clean after contamination. With porous structures such as textiles, however, this is not so trivial. Empa researchers have solved this problem together with experts from BASF, Spiez Laboratory and the Technical University of Berlin: a coating process can now be used to treat fabrics in such a way that bacterial and viral pathogens are killed or inhibited in their growth. In hospitals, the impregnated textiles could be used in future as antimicrobial curtains between patient beds, for example.
“We were looking for a process that reliably prevents germs from contaminating textiles that come into contact with a large number of people during use,” explains Peter Wick from Empa’s “Particles-Biology Interactions” laboratory in St. Gallen. This could break chains of infection in which, for example, multi-resistant bacteria or viral pathogens settle on hospital curtains and can then be spread by people.
Active for months
The researchers ultimately developed a coating process in which disinfectant containing benzalkonium chloride was evenly applied to the hospital curtains. After variables such as concentration, exposure time, processing pressure and drying were optimized, the coating adhered stably to the textiles. But did the coated textiles also have a germicidal effect? This was to be shown by analyzing the antimicrobial activity of the first fabric samples.
“The results of the laboratory tests were very encouraging,” says Wick. When the bacterial cultures of some typical problem germs were incubated with the fabric samples, the coated textile samples inhibited the growth of staphylococci and pseudomonas bacteria, for example. According to the Empa researcher, hospital germs were significantly reduced or even killed after just ten minutes. The coating was also active against viral pathogens: over 99 percent of the viruses tested were killed by the coated fabric samples.
The coatings remained effective even after several months of storage. This allows production in stock. The new process could also be used in the future to quickly and safely treat other textiles, filters or cleaning utensils with antimicrobial agents, for example in the event of an epidemic, emphasizes Empa researcher Wick.
