EPFL develops antibacterial and -viral filters
Laboratory researchers at the Swiss Federal Institute of Technology Lausanne (EPFL) are working on a membrane that not only traps viruses and bacteria, but also destroys them in seconds with light. It can be used in mouth-nose masks as well as in ventilation and air-conditioning systems.
Image of the EPFL laboratory showing an interesting size ratio of bacterial diameters.
EPFL's Laboratory of Complex Matter Physics (LPMC) has discovered that a filter membrane made of titanium oxide nanowires is able to capture pathogens and destroy them with daylight. Masks with this filter can be sterilized and reused thousands of times. This would alleviate bottlenecks and significantly reduce the amount of waste from disposable surgical masks. In addition, these filter membranes would also be usable in ventilation and air conditioning systems.
The environmental impact of used disposable masks, which are made of layers of non-woven polypropylene plastic microfibers, is also not negligible, according to a Communication of the EPFL. Moreover, they merely trap pathogens instead of destroying them. "In a hospital, these masks are stored in special containers and treated accordingly," warns the head of the LPMC, László Forró.
His team's filter material takes advantage of the photocatalytic properties of titanium oxide. "Because our filter absorbs moisture exceptionally well, it can trap droplets that carry viruses and bacteria," Forró said. "This creates a favorable environment for the oxidation process, which is triggered by light."
A corresponding article by the researchers was published on Friday in the scientific journal "Advanced Functional Materials" was published. Based on their results, the researchers assume that the method is successful with a variety of viruses, including SARS-CoV-2. However, this remains to be proven experimentally.
Their article goes on to say that the production of such membranes would be feasible on a large scale. The laboratory's facilities alone are capable of producing material for 80,000 masks per month. The start-up company Swoxid is already preparing to outsource the technology from the lab.
