Self-disinfecting textile could prevent cross-contamination in hospitals
Image credit: Surfaceskins
Researchers at the University of Leeds have developed a novel textile capable of cleaning itself in seconds. It has been incorporated into a device which can be mounted on hospital doors as a more hygienic alternative to metal plates.
The idea of a self-cleaning door plate came to Leeds-based industrial designer Adam Walker seven years ago, while visiting a doctor’s surgery.
“I walked into a surgery and was confronted with a dirty door that I didn’t want to touch and I think that’s a problem most people can identify with having at some point in their life,” he told E&T.
“I did the classic shoulder barge or push-kick to open the door, then proceeded to sit in the waiting room and think that there must be a way to produce an antibacterial door handle or cover that stops you picking up germs.”
According to the National Institute for Care and Excellence, 300,000 patients in England suffer hospital-acquired infections every year at a cost of approximately £1 billion.
Given that they are frequently touched - including by sick patients - doors have been recognised as a ‘weak link’ in hospital hygiene. If a single person with dirty hands (perhaps carrying norovirus or salmonella) passes through a door, every subsequent person passing through is at risk of cross-contamination.
At present, ordinary aluminium or steel door plates in hospitals are wiped down weekly or biweekly. The only self-cleaning door plate available (which is copper-based) takes six to eight hours to disinfect itself, by which point an virus may have spread to dozens of people.
The self-disinfecting device developed at the University of Leeds contains three separate textiles. When a person pushes against it to open a door a trace of alcohol gel is squeezed onto its surface through a membrane of tiny valves or ‘mouths’ which open under pressure. This gel disinfects the surface in seconds and evaporates.
According to the researchers, a particularly challenging stage of the development process was structuring the material such that the reservoir of alcohol gel did not sink to the bottom when mounted vertically on a door. The limited size of the alcohol gel reservoir is such that it needs to be changed every seven days or every 1,000 pushes.
“It’s quite low key, deliberately so,” Walker said. “There are various solutions [to improve hospital hygiene], to make people go out of their way to do something different. Here, you just push open a door plate. So apart from it being slightly spongey rather than a piece of metal, you don’t notice much difference.”
These door pads are not intended to replace handwashing and gel dispensers in hospitals, but to compliment what is already in place. The researchers hope first and foremost that commercialising the device will raise awareness of hand hygiene.
“The whole ethos is to create a product that stops the spread of germs from one person to the next going through a door,” Walker told E&T. “It doesn’t force you to touch a dirty door that you don’t want to touch.”
To test their effectiveness, this novel textile and standard aluminium plates were inoculated with bacteria at levels typical of hospital staff. The new material was found to be able to reduce levels of E. coli, E. faecalis (which can cause life-threatening infection) and Staphylococcus aureus by more than 90 per cent compared with standard aluminium plates.
The product has been named Surfaceskins and is being brought to market by a spin-out from the University of Leeds.
Walker and his colleagues are now developing a rounded version of the device for hospital door handles while looking into other hospital applications, although the self-disinfecting material could have applications across other sectors. It could be used on supermarket trolley handles, cruise ships, in agriculture to prevent the spread of disease among livestock and the researchers have even received an enquiry about using the material to prevent foot infections in expensive racehorses.
While Surfaceskins were designed to mimic ordinary cleaning procedures, many self-cleaning materials are inspired by biological phenomena. The wings of cicadas have inspired self-cleaning, anti-fogging surfaces and the remarkable toes of geckoes have inspired self-cleaning adhesive tape.