Scientists at Queen's University Belfast have developed a plastic film that is self-sterilising and could make it harder for infections, including Covid, to spread in hospitals and care homes. The plastic film is cheap to produce and can be fashioned into protective aprons and other clothing.
The plastic film works by reacting with light to release chemicals that break viruses, killing them by the million, even in tough species that stay on clothes and surfaces.
Studies had shown that under certain conditions, the Covid virus was able to survive for up to 72 hours on some surfaces and under certain conditions. Other viruses can survive for longer - the norovirus (winter vomiting bug) can survive outside the body to two weeks while waiting for someone new to infect.
The aim of the research was to create a material that viruses could not survive on. While copper is known to kill microbes on contact, it is not very flexible. The new plastic contains nanoparticles of titanium dioxide, which react with ultraviolet light (which can be the tiny amount emitted by a fluorescent tube) to release molecules called reactive oxygen species. Theses react with the genetic material of the virus, the proteins it uses to enter the body, and the fatty sphere around it, resulting in a dead virus.
In the laboratory the material was tested against four types of virus: two influenza viruses, the Covid virus and a picornavirus, which is a very stable virus outside the body. Large amounts (far more than would start an infection) of each of these viruses were placed on the new plastic and went down down from one million viruses to nothing. The effect is seen in less than one hour and maximum death in two hours. In real conditions far fewer virus particles would be present, so it is likely there would be an effect in the first few minutes.
Prof. Andrew Mills of the university's chemistry department said "This film could replace many of the disposable plastic films used in the healthcare industry as it has the added value of being self-sterilising at no real extra cost."
Current personal protective equipment used in hospitals works well, but infections can take place when taking off or putting on PPE. The team are also investigating its use for hospital tablecloths and curtains and use in the food processing industry. Real world trials will be needed to work out how much of a difference it would make.
Source: Self-sterilising plastic kills viruses like Covid by James Gallagher, BBC News 9th Sept. 2022
