With the COVID-19 pandemic, masks have become an essential part of our daily lives. They are integral to controlling the community spread of the novel coronavirus. But what if they could do more?

Singapore-based scientists have envisioned "smart masks" that work as a preventive tool and measure the wearer's vital signs.

The team from the Nanyang Technological University (NTU) and the Agency for Science, Technology and Research (A*Star) have developed sensors which can be attached to any face mask and capture skin temperature, blood oxygen saturation, blood pressure and heart rate - all health indicators that are associated with COVID-19.

"These chips are meant to be what we call 'plug and play' systems and they are meant to be easily attached to any sort of mask, could be a surgical mask, could be a cloth mask, it could be an N-95," said Professor Loh Xian Jun, one of the scientists behind the project.

Professor Loh, an executive director at A* Star's Institute of Materials Research and Engineering, goes on to explain that the sensors have an "inbuilt LED device that allows it to shine light through the skin and onto the capillaries" on a person's face.

"We use the change in the size of the capillaries as an indicator of how the blood pressure changes. So, for example, when the blood pressure is high, we can expect that the blood capillaries to be expanded and the change in the size can be measured by the LED," he added.

Once captured, the data can be relayed to a tablet, computer, or smartphone using Bluetooth signals.

Professor Chen Xiaodong from the School of Materials Science and Engineering at NTU says the idea came to him during Singapore's circuit breaker or partial lockdown period earlier this year.

"I think for us, as researchers, as professors we wanted to do something where we could benefit the community," said Professor Chen.

The team believes that these "smart masks" would be useful for mass health monitoring in places like hospitals and nursing homes.

Nurses and healthcare workers are required to regularly monitor patient vitals and take temperature readings. They are forced to drag equipment from room to room to carry out such monitoring. This is not only inconvenient but also further increases their risk of infection.

"We felt that this will cause a lot of danger to the medical workers, to be exposed to the patient when they are taking the vital sign readings, and this is something that we actually tried to solve," explained Professor Loh.

"It is mostly for continuous measurement. It will help the doctor to continually know a patient's status rather than you measure temperature every few minutes," added Professor Chen.

"I think this is a great invention, in fact, not just do healthcare workers need it, patients need it, even non-COVID patients could have their data monitored very regularly. There are already temperature sensors that are made very portable and this is an extra armament," said Dr. Leong Hoe Nam, an infectious disease specialist at Singapore's Mount Elizabeth Novena Hospital.

However, Dr. Leong has raised some concerns with regard to the location of the sensors.

"Having the measurement in a face mask, something touching the cheek, I think it is a very weird feeling. What I would rather have is that the same technology is applied on an armband or on the wrist. In other words, it is a great invention, but we may have to tweak it a little bit for a greater, more effective push and acceptance."

Responding to Dr. Leong's comments, Professor Loh added, "We do really recognize such comments. If you put a lot of rigid sensors on the face, you will not feel comfortable. But now we can make these sensors in generation four, this is very light, it is very small, just the size of a nail."

To make the chip less abrasive for the wearer, the team integrated it into an artificial skin-like silicone material. The material is extremely flexible, durable and water-resistant.

Professor Chen explained that the current model costs about 50 Singapore dollars ($37.50) in terms of cost. But if production is ramped up on a mass scale, the price could be brought down to cost less than 20 Singapore dollars ($15).

The researchers are currently in talks with partners in the healthcare sector to conduct clinical trials and assess the technology's accuracy.

Their current lab-based data shows a marginal deviation of 3 to 5 percent when measurements by smart masks are compared to standard medical equipment. They are hoping to validate their data and go commercial next year.

Professor Chen believes that the technology could be especially useful in countries where the healthcare system is strained due to sheer numbers of cases.

"I believe that such technology would be very useful for countries which have a large number of infected. Then you do not need to spend so much manpower to monitor each of them individually. You place these sensors, and then the doctor just stays in the workstation and can get all the data on their iPad or computer," concludes Professor Chen.