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.
Here's how one doctor overcame extraordinary odds to help create the birth control pill
Dr. Percy Julian had so many personal and professional obstacles throughout his life, it’s amazing he was able to accomplish anything at all. But this hidden figure not only overcame these incredible obstacles, he also laid the foundation for the creation of the birth control pill.
Julian’s first obstacle was growing up in the Jim Crow-era south in the early part of the twentieth century, where racial segregation kept many African-Americans out of schools, libraries, parks, restaurants, and more. Despite limited opportunities and education, Julian was accepted to DePauw University in Indiana, where he majored in chemistry. But in college, Julian encountered another obstacle: he wasn’t allowed to stay in DePauw’s student housing because of segregation. Julian found lodging in an off-campus boarding house that refused to serve him meals. To pay for his room, board, and food, Julian waited tables and fired furnaces while he studied chemistry full-time. Incredibly, he graduated in 1920 as valedictorian of his class.
After graduation, Julian landed a fellowship at Harvard University to study chemistry—but here, Julian ran into yet another obstacle. Harvard thought that white students would resent being taught by Julian, an African-American man, so they withdrew his teaching assistantship. Julian instead decided to complete his PhD at the University of Vienna in Austria. When he did, he became one of the first African Americans to ever receive a PhD in chemistry.
Julian received offers for professorships, fellowships, and jobs throughout the 1930s, due to his impressive qualifications—but these offers were almost always revoked when schools or potential employers found out Julian was black. In one instance, Julian was offered a job at the Institute of Paper Chemistory in Appleton, Wisconsin—but Appleton, like many cities in the United States at the time, was known as a “sundown town,” which meant that black people weren’t allowed to be there after dark. As a result, Julian lost the job.
During this time, Julian became an expert at synthesis, which is the process of turning one substance into another through a series of planned chemical reactions. Julian synthesized a plant compound called physostigmine, which would later become a treatment for an eye disease called glaucoma.
In 1936, Julian was finally able to land—and keep—a job at Glidden, and there he found a way to extract soybean protein. This was used to produce a fire-retardant foam used in fire extinguishers to smother oil and gasoline fires aboard ships and aircraft carriers, and it ended up saving the lives of thousands of soldiers during World War II.
At Glidden, Julian found a way to synthesize human sex hormones such as progesterone, estrogen, and testosterone, from plants. This was a hugely profitable discovery for his company—but it also meant that clinicians now had huge quantities of these hormones, making hormone therapy cheaper and easier to come by. His work also laid the foundation for the creation of hormonal birth control: Without the ability to synthesize these hormones, hormonal birth control would not exist.
Julian left Glidden in the 1950s and formed his own company, called Julian Laboratories, outside of Chicago, where he manufactured steroids and conducted his own research. The company turned profitable within a year, but even so Julian’s obstacles weren’t over. In 1950 and 1951, Julian’s home was firebombed and attacked with dynamite, with his family inside. Julian often had to sit out on the front porch of his home with a shotgun to protect his family from violence.
But despite years of racism and violence, Julian’s story has a happy ending. Julian’s family was eventually welcomed into the neighborhood and protected from future attacks (Julian’s daughter lives there to this day). Julian then became one of the country’s first black millionaires when he sold his company in the 1960s.
When Julian passed away at the age of 76, he had more than 130 chemical patents to his name and left behind a body of work that benefits people to this day.
Therapies for Healthy Aging with Dr. Alexandra Bause
My guest today is Dr. Alexandra Bause, a biologist who has dedicated her career to advancing health, medicine and healthier human lifespans. Dr. Bause co-founded a company called Apollo Health Ventures in 2017. Currently a venture partner at Apollo, she's immersed in the discoveries underway in Apollo’s Venture Lab while the company focuses on assembling a team of investors to support progress. Dr. Bause and Apollo Health Ventures say that biotech is at “an inflection point” and is set to become a driver of important change and economic value.
Previously, Dr. Bause worked at the Boston Consulting Group in its healthcare practice specializing in biopharma strategy, among other priorities
She did her PhD studies at Harvard Medical School focusing on molecular mechanisms that contribute to cellular aging, and she’s also a trained pharmacist
In the episode, we talk about the present and future of therapeutics that could increase people’s spans of health, the benefits of certain lifestyle practice, the best use of electronic wearables for these purposes, and much more.
Dr. Bause is at the forefront of developing interventions that target the aging process with the aim of ensuring that all of us can have healthier, more productive lifespans.