Scientists are developing a smartphone app that can detect COVID-19 in saliva in about 10 minutes.
The technology combines a phone with a small microscope that scans a saliva sample to detect evidence of the virus.
Designed by the University of Arizona, the team’s goal is to combine the speed of an antigen test with the accuracy of a polymerase chain reaction test or PCR.
The technology was originally developed as an economical method to identify norovirus, but was modified in light of the ongoing pandemic.
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Scientists at the University of Arizona have developed a smartphone app that works with a microscope to test saliva samples for COVID-19. The process only takes about 10 to 15 minutes and the components cost about $ 45
The process, reported in the journal Nature Protocols, consists of a microscope and a sheet coated with wax, called microfluidic paper, which guides the sample through certain channels.
After placing a saliva sample on the paper, a patient introduces antibodies with fluorescent beads.
If there are enough coronavirus particles, the antibodies will adhere to each of them.
“Under a microscope, pathogenic particles appear as small groups of fluorescent beads, which the user can count on,” the researchers explained.
After placing a saliva sample on a sheet of microfluidic paper, the user introduces antibodies with fluorescent beads. If there are enough coronavirus particles, the antibodies will adhere to each of them. The virus particles will look like small groups of fluorescent pearls, which the user will be able to count
According to the researchers, the whole process (adding pearls to the sample, soaking the sample paper, then taking a picture of it on the smartphone under a microscope and counting the pearls) takes 10 to 15 minutes.
Katie Sosnowski, a doctoral student in the university’s biomedical engineering department, said it was “great” to work on a test that offered “quick results that are also accurate.”
“I have a couple of friends who had COVID-19 very frustrated, because their PCR results took six or seven days or they got false negatives from fast antigen tests,” he said.
“But when they got the final PCR tests, they found out they had been sick, as they suspected.”
The researchers also developed a 3D-printed housing for fixing the microscope and microfluidic paper chip. They also developed a method called “adaptive threshold,” which uses AI to account for differences in the type of phone used, paper quality, and other factors.
The team, led by biomedical engineering professor Jeong-Yeol Yoon, originally reported on their work in a 2019 article in ACS Omega magazine.
At the time, they were thinking of quick and easy ways to test norovirus, the highly contagious virus that often breaks out on cruises, but they believe it could be adapted to identify any number of viral infections.
For the coronavirus kit, the team added a 3D printed housing for fixing the microscope and microfluidic paper chip.
A method called “adaptive threshold” was also introduced that uses artificial intelligence to set the danger threshold and take into account differences in the type of phone used, paper quality, and other factors.
“We sketched it out so other scientists could basically repeat what we did and create a norovirus detection device,” said Lane Breshears, a doctoral student studying at Yoon.
“Our goal is that if you want to adapt it to something else, like we adapted it for COVID-19, you have all the ingredients you need to basically make your own device.”
Most methods to detect COVID-19 or other pathogens are time consuming, costly, and require medical experience.
The total cost of the components for the Arizona U test is about $ 45 and it’s easy enough for a layman to do so after watching a short instructional video.
The technology still has a long way to go before it hits the market, but researchers hope to get permission to test samples of students who are already taking COVID-19 tests on campus using other established methods.
Ultimately, they plan to distribute the device across campus so that an RA can test students in a dormitory.
“Adapting a method designed to detect norovirus (another highly contagious pathogen) is a prime example of our researchers pivoting in the face of the pandemic,” said University of Arizona President Robert C. Robbins .
“This promising technology could enable us to provide fast, accurate and affordable testing to the campus community frequently and easily.”
Yoon’s team also conceived of adapting the technology so that it didn’t even need a microscope, just an app, and a microflunic chip with a special QR code.
It would leave a little more room for error, but it would not require training and could even be self-administered.
Since the arrival of the new coronavirus, scientists around the world have been working to develop faster, cheaper, and more convenient test methods.
Current tests require a swab of the nose and back of the throat, usually in a clinic, which can take time and be unpleasant.
In May 2020, researchers at the University of Pittsburgh announced that they were working on an application that uses artificial intelligence to analyze sounds coming from someone’s airways and determine if they matched those of a COVID-19 patient.
Developers are working on smartphone apps that can accurately test the COVID-19, even though they are cheap, comfortable, and painless. If successful, it would quickly increase testing and allow people to avoid meeting in clinics or hospitals.
Users should use an adapter as a mouthpiece so that the phone’s microphone and speaker can record and transmit acoustic signals from their airways.
The goal is to create a simple, inexpensive system to test COVID-19 from home “and quickly and effectively identify carriers of viral diseases,” said Wei Gao, lead researcher.
“We hope this work will also help identify negative cases caused by other illnesses with similar symptoms and therefore help eliminate unnecessary hospital visits during this pandemic.”
A separate team from Switzerland is trying to develop a similar system through coughing.
It seems clear that a high proportion [of coronavirus patients] having this type of dry cough that is different from the flu or allergies, ”Tomas Teijeiro, lead researcher on the Coughvid project, told the Wall Street Journal.
The creators of another app, PocDoc, say it can be combined with the phone’s camera to analyze a blood sample and provide quick results for a COVID-19 antibody test.
A user punctures their finger, puts a drop of blood on the test slide, and then takes a picture. The software is designed to detect small color changes when COVID antibodies are present and provide results in five minutes.
“COVID-19 has accelerated the requirement for all kinds of innovative healthcare technology,” said Steve Roest, CEO of PocDoc.