Picture this: you’re standing on a bus, wearing a face mask, and an alert pops up on your phone. It notifies you that you’ve been in contact with someone who has Covid.
Rather than heading in to work, or to visit your grandma, you decide to stay home that week just in case you’re infectious. The chain of transmission is broken.
Face masks have played a huge part in protecting people from Covid-19 during the pandemic – and now, they’ve had something of an upgrade, as scientists in China have created a highly sensitive mask that can detect common respiratory viruses – we’re talking Covid-19, flu and even bird flu – floating in the air.
The mask, presented in the journal Matter, can alert the wearers via their mobile devices within 10 minutes if virus particles are present in the surrounding air.
Covid-19 is mainly spread through small droplets and aerosols released when infected people talk, cough and sneeze. These virus-containing molecules can remain suspended in the air for a long time, which is why face masks are so useful.
Study author Yin Fang, a material scientist at Shanghai Tongji University, in China, said: “Previous research has shown face mask-wearing can reduce the risk of spreading and contracting the disease. So, we wanted to create a mask that can detect the presence of virus in the air and alert the wearer.”
When scientists tested the new mask in an enclosed chamber, the sensor responded to as little as 0.3 microliters of liquid containing viral proteins.
To put this into perspective, this is about 70 to 560 times less than the volume of liquid produced in one sneeze and much less than the volume produced by coughing or talking, Fang said. So it can basically detect either droplets or aerosols.
The mask is fitted with aptamers, which are a type of synthetic molecule that can identify unique proteins of pathogens.
The team modified the mask’s sensor with three types of aptamers, which can simultaneously recognise surface proteins on SARS-CoV-2 (the coronavirus), H5N1 (bird flu), and H1N1 (influenza).
Once the aptamers bind to the target proteins in the air, an ion-gated transistor – which is incredibly sensitive – amplifies the signal and alerts the wearer they’ve been in contact with Covid-19 (or another respiratory virus) via their phones.
The mask would work particularly well in spaces with poor ventilation, such as elevators or enclosed rooms, where the risk of getting infected is high, said Fang.
What’s more, if a new respiratory virus were to emerge in the future, they’d be able to easily update the sensor’s design for detecting the new pathogens.
The team now has plans to shorten the detection time and further increase the sensitivity of the sensor.
“Currently, doctors have been relying heavily on their experiences in diagnosing and treating diseases. But with richer data collected by wearable devices, disease diagnosis and treatment can become more precise,” Fang concluded.