Biology and Medicine are at the forefront of the fight against the coronavirus. And physics is just as important, especially when it comes to disinfection. But how?
SARS-CoV-2 has amplified the meaning of the word “disinfection“. Common disinfectants, alcohol and masks have become our most trusted companions. The latter has raised an issue that is much less talked about but which, sooner or later, we’ll have to deal with: the disposal of masks.
To date, millions of different types of masks have already been thrown into the trash, and we know that human beings are not necessarily role models when it comes to the environment. How many million masks will be used in the coming months — maybe even years? The problem of their disposal and the subsequent ecological damage is a problem that we must tackle, ourselves, even from the beginning.
Rapid UV disinfection
One thing Scientists usually do well is work together. Not only within the same discipline, but also between various disciplines; exchanging opinions and above all, trying to solve a problem with different approaches and technologies.
Researchers at the National Institute of Astrophysics (INAF) in Brera, Italy have confronted the question: “how can we disinfect objects and air from the Coronavirus?”.
INAF researchers work in mechanics, optics, chemistry, physics and electronics to support astronomical investigations. They’re therefore not virus experts, but are experts in ultraviolet (UV) rays that have the ability to kill viruses.
The concept is to develop devices that release UV radiation and that can disinfect in a very short time, ideally instantaneously — the object or even the air that is irradiated.
Which devices are being studied?
Let’s start with sterilizers that sanitize the air emitted by the COVID-19 patient. Most current masks have a filter that stops droplets of saliva or mucus containing the virus. The filter has a limited retention capacity and therefore needs to be changed; in most cases, it’s the entire mask that needs to be discarded. The solution of the Brera researchers is based on a permanent device that self-disinfects itself.
They then move on to disinfection systems for home, workplaces, or hospital ventilation systems. Also, in this case, a self-disinfecting device could be used. To finish, on to sanitizers for everyday objects, such as smartphones, keys and cash.
These are therefore ecological solutions, as they’re reusable (several times), and based on UV rays that we’ve learned to modulate in their intensity to be effective and not harmful to humans.
UV rays for masks as well
Returning to masks, a use of the UV device that researchers in Brera are developing, is to make them reusable by sterilizing them, and thus extending their life with obvious savings for those who must buy them, and a subsequent reduction in the risk of remaining without them, also reducing the environmental impact.
Since surgical masks, for example, have many folds, the risk is that UV rays sterilize only parts of the mask. One of the solutions that have been considered is the use of ozone, which is produced by certain short-wavelength UV lamps. So, using the same source (but only modulating the wavelength) as if it were a small radio in search of the best signal, you could sterilize all parts of an object and then reuse it.
Not being virus experts and not being able to manipulate them, INAF researchers collaborate with the Sacco Hospital in Milan, which deals with the treatment of SARS-CoV-2 in a protected and controlled environment, in order to better understand the doses of UV radiation required to inactivate the virus.
This post is also available in: Italiano