Scientists are developing a smartphone app that can detect COVID-19 in saliva in about 10 minutes.
The technology pairs a phone with a small microscope that analyzes a saliva sample to highlight 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 or PCR test.
The technology was originally developed as a cheap method of identifying norovirus, but has been modified in light of the ongoing pandemic.
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Scientists at the University of Arizona have developed a smartphone application 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 covered with wax, called microfluidic paper, which guides the sample through certain channels.
After placing a saliva sample on paper, a patient introduces antibodies with fluorescent beads.
If enough coronavirus particles are present, the antibodies will attach to each.
“Under the microscope, the pathogen particles appear in the form of small clusters of fluorescent beads, which the user can then count,” the researchers explained.
After placing a saliva sample on a sheet of microfluidic paper, the user introduces antibodies with fluorescent beads. If enough coronavirus particles are present, the antibodies will attach to each. The virus particles will look like small clusters of fluorescent beads, which the user can then count.
According to the researchers, the whole process – adding beads to the sample, soaking the paper in the sample, then taking a photo of it on a smartphone under a microscope and counting the beads – takes 10-15 minutes.
Katie Sosnowski, a doctoral student in the university’s biomedical engineering department, said it was “cool” to work on a test that would provide “fast results that are also accurate.”
“I have some friends who had COVID-19 who were very frustrated because the PCR results lasted six or seven days or they received negative results from the rapid antigen tests,” she said.
“But when they received the last PCR tests, they found out they were sick, as they had suspected.”
The researchers also developed a 3D printed case for attaching the microscope and the microfluidic paper chip. They also developed a method called ‘adaptive thresholds’, which uses AI to take into account the differences between the type of phone used, the quality of the paper and other factors.
The team, led by biomedical engineering professor Jeong-Yeol Yoon, initially reported on their work in a 2019 paper in ACS Omega magazine.
At the time, they were thinking of quick and easy ways to test norovirus, the highly contagious virus that often appears on cruise ships, but I think it could be adapted to identify any number of viral infections.
For the coronavirus kit, the team added a 3D printed case for attaching the microscope and the microfluidic paper chip.
A method called “adaptive threshold” has also been introduced, which uses artificial intelligence to set the danger threshold and to take into account the differences between the type of phone used, the quality of the paper and other factors.
“We designed it so that other scientists could repeat what we did and create a norovirus detection device,” said Lane Breshears, a doctoral student studying under Yoon.
“Our goal is that if you want to adapt it for something else, as we adapted it for COVID-19, you have all the ingredients you need to create your own device.”
Most methods of detecting COVID-19 or other pathogens are time consuming, costly and require medical expertise.
The total cost of components for the Arizona U-test is about $ 45, and it’s pretty easy for a layman to do after watching a short instructional video.
The technology still has a way to go before it goes on the market, but researchers hope to get permission to test samples from students who are already being tested for COVID-19 on campus, through other established methods.
Finally, consider distributing the device on campus so that an RA can test students in a dormitory.
“Adapting a method designed to detect norovirus – another highly contagious pathogen – is a remarkable example of our researchers pivoting in the face of the pandemic,” said University of Arizona President Robert C. Robbins.
“This promising technology could allow us to provide quick, accurate and accessible tests to the campus community frequently and easily.”
Yoon’s team also designed to adapt the technology so that it doesn’t even need a microscope, just an application and a microfluidic 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 testing methods.
Current testing requires a tampon from the nose and back of the neck, usually in a clinic, which can be time consuming and 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 from one’s airways and determine if they match those of a COVID-19 patient.
Developers are working on smartphone applications that can accurately test COVID-19, yet are inexpensive, convenient and painless. If successful, it would rapidly increase testing and allow people to avoid gathering at clinics or hospitals
Users should use an adapter as a mouthpiece so that the phone’s microphone and speaker can record and transmit sound signals from the airways.
The goal is to create a cheap and simple system that allows people to be tested for COVID-19 from their own home and quickly and effectively identify carriers of viral diseases, said lead researcher Wei Gao.
We hope that this work will also help identify negative cases caused by other diseases 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 using cough.
“It simply came to our notice then [of coronavirus patients] they have this type of dry cough other than the flu or allergies, ”Tomas Teijeiro, principal investigator for the Coughvid project, told the Wall Street Journal.
The makers 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 taps their finger, puts a drop of blood on the test slide, and then takes a photo. The software is designed to detect small discoloration when COVID antibodies are present and deliver results within five minutes.
“COVID-19 has accelerated the demand for innovative health technologies of all kinds,” said Steve Roest, CEO of PocDoc.