Researchers Are Designing a Biosensor to Detect Viruses in Transit Hubs and Hospitals
The unprecedented scale and impact of the COVID-19 pandemic has caused scientists and engineers around the world to stop whatever they were working on and shift their research toward understanding a novel virus instead.
"We have confidence that we can use our system in the next pandemic."
For Guangyu Qiu, normally an environmental engineer at the Swiss Federal Laboratories for Materials Science and Technology, that means finding a clever way to take his work on detecting pollution in the air and apply it to living pathogens instead. He's developing a new type of biosensor to make disease diagnostics and detection faster and more accurate than what's currently available.
But even though this pandemic was the impetus for designing a new biosensor, Qiu actually has his eye on future disease outbreaks. He admits that it's unlikely his device will play a role in quelling this virus, but says researchers already need to be thinking about how to make better tools to fight the next one — because there will be a next one.
"In the last 20 years, there [have been] three different coronavirus [outbreaks] ... so we have to prepare for the coming one," Qiu says. "We have confidence that we can use our system in the next pandemic."
"A Really, Really Neat Idea"
His main concern is the diagnostic tool that's currently front and center for testing patients for SARS-Cov-2, the virus causing the novel coronavirus disease. The tool, called PCR (short for reverse transcription polymerase chain reaction), is the gold standard because it excels at detecting viruses in even very small samples of mucus. PCR can amplify genetic material in the limited sample and look for a genetic code matching the virus in question. But in many parts of the world, mucus samples have to be sent out to laboratories for that work, and results can take days to return. PCR is also notoriously prone to false positives and negatives.
"I read a lot of newspapers that report[ed] ... a lot of false negative or false positive results at the very beginning of the outbreak," Qiu says. "It's not good for protecting people to prevent further transmission of the disease."
So he set out to build a more sensitive device—one that's less likely to give you a false result. Qiu's biosensor relies on an idea similar to the dual-factor authentication required of anyone trying to access a secure webpage. Instead of verifying that a virus is really present by using one way of detecting genetic code, as with PCR, this biosensor asks for two forms of ID.
SARS-CoV-2 is what's called an RNA virus, which means it has a single strand of genetic code, unlike double-stranded DNA. Inside Qiu's biosensor are receptors with the complementary code for this particular virus' RNA; if the virus is present, its RNA will bind with the receptors, locking together like velcro. The biosensor also contains a prism and a laser that work together to verify that this RNA really belongs to SARS-CoV-2 by looking for a specific wavelength of light and temperature.
If the biosensor doesn't detect either, or only registers a match for one and not the other, then it can't produce a positive result. This multi-step authentication process helps make sure that the RNA binding with the receptors isn't a genetically similar coronavirus like SARS-CoV, known for its 2003 outbreak, or MERS-CoV, which caused an epidemic in 2012.
It could also be fitted to detect future novel viruses once their genomes are sequenced.
The dual-feature design of this biosensor "is a really, really neat idea that I have not seen before with other sensor technology," says Erin Bromage, a professor of infection and immunology at the University of Massachusetts Dartmouth; he was not involved in designing or testing Qiu's biosensor. "It makes you feel more secure that when you have a positive, you've really got a positive."
The light and temperature sensors are not in themselves new inventions, but the combination is a first. The part of the device that uses light to detect particles is actually central to Qiu's normal stream of environmental research, and is a versatile tool he's been working with for a long time to detect aerosols in the atmosphere and heavy metals in drinking water.
Bromage says this is a plus. "It's not high-risk in the sense that how they do this is unique, or not validated. They've taken aspects of really proven technology and sort of combined it together."
This new biosensor is still a prototype that will take at least another 12 months to validate in real world scenarios, though. The device is sound from a biological perspective and is sensitive enough to reliably detect SARS-CoV-2 — and to not be tricked by genetically similar viruses like SARS-CoV — but there is still a lot of engineering work that needs to be done in order for it to work outside the lab. Qiu says it's unlikely that the sensor will help minimize the impact of this pandemic, but the RNA receptors, prism, and laser inside the device can be customized to detect other viruses that may crop up in the future.
"If we choose another sequence—like SARS, like MERS, or like normal seasonal flu—we can detect other viruses, or even bacteria," Qiu says. "This device is very flexible."
It could also be fitted to detect future novel viruses once their genomes are sequenced.
The Long-Term Vision: Hospitals and Transit Hubs
The device has been designed to connect with two other systems: an air sampler and a microprocessor because the goal is to make it portable, and able to pick up samples from the air in hospitals or public areas like train stations or airports. A virus could hopefully be detected before it silently spreads and erupts into another global pandemic. In the case of SARS-CoV-2, there has been conflicting research about whether or not the virus is truly airborne (though it can be spread by droplets that briefly move through the air after a cough or sneeze), whereas the highly contagious RNA virus that causes measles can remain in the air for up to two hours.
"They've got a lot on the front end to work out," Bromage says. "They've got to work out how to capture and concentrate a virus, extract the RNA from the virus, and then get it onto the sensor. That's some pretty big hurdles, and may take some engineering that doesn't exist right now. But, if they can do that, then that works out really quite well."
One of the major obstacles in containing the COVID-19 pandemic has been in deploying accurate, quick tools that can be used for early detection of a virus outbreak and for later tracing its spread. That will still be true the next time a novel virus rears its head, and it's why Qiu feels that even if his biosensor can't help just yet, the research is still worth the effort.
It could also be fitted to detect future novel viruses once their genomes are sequenced.
The dual-feature design of this biosensor "is a really, really neat idea that I have not seen before with other sensor technology," says Erin Bromage, a professor of infection and immunology at the University of Massachusetts Dartmouth; he was not involved in designing or testing Qiu's biosensor. "It makes you feel more secure that when you have a positive, you've really got a positive."
The light and temperature sensors are not in themselves new inventions, but the combination is a first. The part of the device that uses light to detect particles is actually central to Qiu's normal stream of environmental research, and is a versatile tool he's been working with for a long time to detect aerosols in the atmosphere and heavy metals in drinking water.
Bromage says this is a plus. "It's not high-risk in the sense that how they do this is unique, or not validated. They've taken aspects of really proven technology and sort of combined it together."
This new biosensor is still a prototype that will take at least another 12 months to validate in real world scenarios, though. The device is sound from a biological perspective and is sensitive enough to reliably detect SARS-CoV-2 — and to not be tricked by genetically similar viruses like SARS-CoV — but there is still a lot of engineering work that needs to be done in order for it to work outside the lab. Qiu says it's unlikely that the sensor will help minimize the impact of this pandemic, but the RNA receptors, prism, and laser inside the device can be customized to detect other viruses that may crop up in the future.
"If we choose another sequence—like SARS, like MERS, or like normal seasonal flu—we can detect other viruses, or even bacteria," Qiu says. "This device is very flexible."
It could also be fitted to detect future novel viruses once their genomes are sequenced.
The Long-Term Vision: Hospitals and Transit Hubs
The device has been designed to connect with two other systems: an air sampler and a microprocessor because the goal is to make it portable, and able to pick up samples from the air in hospitals or public areas like train stations or airports. A virus could hopefully be detected before it silently spreads and erupts into another global pandemic. In the case of SARS-CoV-2, there has been conflicting research about whether or not the virus is truly airborne (though it can be spread by droplets that briefly move through the air after a cough or sneeze), whereas the highly contagious RNA virus that causes measles can remain in the air for up to two hours.
"They've got a lot on the front end to work out," Bromage says. "They've got to work out how to capture and concentrate a virus, extract the RNA from the virus, and then get it onto the sensor. That's some pretty big hurdles, and may take some engineering that doesn't exist right now. But, if they can do that, then that works out really quite well."
One of the major obstacles in containing the COVID-19 pandemic has been in deploying accurate, quick tools that can be used for early detection of a virus outbreak and for later tracing its spread. That will still be true the next time a novel virus rears its head, and it's why Qiu feels that even if his biosensor can't help just yet, the research is still worth the effort.
A sleek, four-foot tall white robot glides across a cafe storefront in Tokyo’s Nihonbashi district, holding a two-tiered serving tray full of tea sandwiches and pastries. The cafe’s patrons smile and say thanks as they take the tray—but it’s not the robot they’re thanking. Instead, the patrons are talking to the person controlling the robot—a restaurant employee who operates the avatar from the comfort of their home.
It’s a typical scene at DAWN, short for Diverse Avatar Working Network—a cafe that launched in Tokyo six years ago as an experimental pop-up and quickly became an overnight success. Today, the cafe is a permanent fixture in Nihonbashi, staffing roughly 60 remote workers who control the robots remotely and communicate to customers via a built-in microphone.
More than just a creative idea, however, DAWN is being hailed as a life-changing opportunity. The workers who control the robots remotely (known as “pilots”) all have disabilities that limit their ability to move around freely and travel outside their homes. Worldwide, an estimated 16 percent of the global population lives with a significant disability—and according to the World Health Organization, these disabilities give rise to other problems, such as exclusion from education, unemployment, and poverty.
These are all problems that Kentaro Yoshifuji, founder and CEO of Ory Laboratory, which supplies the robot servers at DAWN, is looking to correct. Yoshifuji, who was bedridden for several years in high school due to an undisclosed health problem, launched the company to help enable people who are house-bound or bedridden to more fully participate in society, as well as end the loneliness, isolation, and feelings of worthlessness that can sometimes go hand-in-hand with being disabled.
“It’s heartbreaking to think that [people with disabilities] feel they are a burden to society, or that they fear their families suffer by caring for them,” said Yoshifuji in an interview in 2020. “We are dedicating ourselves to providing workable, technology-based solutions. That is our purpose.”
Shota Kuwahara, a DAWN employee with muscular dystrophy. Ory Labs, Inc.
Wanting to connect with others and feel useful is a common sentiment that’s shared by the workers at DAWN. Marianne, a mother of two who lives near Mt. Fuji, Japan, is functionally disabled due to chronic pain and fatigue. Working at DAWN has allowed Marianne to provide for her family as well as help alleviate her loneliness and grief.Shota, Kuwahara, a DAWN employee with muscular dystrophy, agrees. "There are many difficulties in my daily life, but I believe my life has a purpose and is not being wasted," he says. "Being useful, able to help other people, even feeling needed by others, is so motivational."
When a patient is diagnosed with early-stage breast cancer, having surgery to remove the tumor is considered the standard of care. But what happens when a patient can’t have surgery?
Whether it’s due to high blood pressure, advanced age, heart issues, or other reasons, some breast cancer patients don’t qualify for a lumpectomy—one of the most common treatment options for early-stage breast cancer. A lumpectomy surgically removes the tumor while keeping the patient’s breast intact, while a mastectomy removes the entire breast and nearby lymph nodes.
Fortunately, a new technique called cryoablation is now available for breast cancer patients who either aren’t candidates for surgery or don’t feel comfortable undergoing a surgical procedure. With cryoablation, doctors use an ultrasound or CT scan to locate any tumors inside the patient’s breast. They then insert small, needle-like probes into the patient's breast which create an “ice ball” that surrounds the tumor and kills the cancer cells.
Cryoablation has been used for decades to treat cancers of the kidneys and liver—but only in the past few years have doctors been able to use the procedure to treat breast cancer patients. And while clinical trials have shown that cryoablation works for tumors smaller than 1.5 centimeters, a recent clinical trial at Memorial Sloan Kettering Cancer Center in New York has shown that it can work for larger tumors, too.
In this study, doctors performed cryoablation on patients whose tumors were, on average, 2.5 centimeters. The cryoablation procedure lasted for about 30 minutes, and patients were able to go home on the same day following treatment. Doctors then followed up with the patients after 16 months. In the follow-up, doctors found the recurrence rate for tumors after using cryoablation was only 10 percent.
For patients who don’t qualify for surgery, radiation and hormonal therapy is typically used to treat tumors. However, said Yolanda Brice, M.D., an interventional radiologist at Memorial Sloan Kettering Cancer Center, “when treated with only radiation and hormonal therapy, the tumors will eventually return.” Cryotherapy, Brice said, could be a more effective way to treat cancer for patients who can’t have surgery.
“The fact that we only saw a 10 percent recurrence rate in our study is incredibly promising,” she said.