Ohio State team of researchers developing DNA-based rapid diagnostic test for COVID-19

Posted: March 30, 2021
. ‘Hinge’ DNA origami biosensor designed by Professor Carlos Castro’s lab to detect and respond to SARS-CoV-2 viral RNA, the virus that causes COVID-19. (Left) COVID-19 Biosensor closed and ready to sense a specific sequence of SARS-CoV-2 viral RNA. (Right) Upon detection, the COVID-19 Biosensor is opened to allow for a detectable fluorescent signal. The COVID-19 Biosensor will lead to development of a rapid molecular COVID-19 diagnostic test.
‘Hinge’ DNA origami biosensor designed by Professor Carlos Castro’s lab to detect and respond to SARS-CoV-2 viral RNA, the virus that causes COVID-19. (Left) COVID-19 Biosensor closed and ready to sense a specific sequence of SARS-CoV-2 viral RNA. (Right) Upon detection, the COVID-19 Biosensor is opened to allow for a detectable fluorescent signal. The COVID-19 Biosensor will lead to development of a rapid molecular COVID-19 diagnostic test.

To ensure a safe return to society, quick, reliable testing is required to identify COVID-19, now considered an endemic disease. To meet this need an Ohio State team of researchers led by mechanical and aerospace engineering professor Carlos Castro are developing a rapid diagnostic test for COVID-19 using a DNA-based nanotechnology.

The target product is a bio-sensing device in the form of a disposable kit to be used at point-of-care or in clinical labs for the rapid diagnosis of patients with COVID-19, according to Christopher Lucas, a research scientist at Ohio State’s Nanoengineering and Biodesign Laboratory.

Chris Lucas

In contrast to current, molecular-based COVID-19 testing, these tests are faster – while retaining accuracy. The disposable tests are also more accessible for underserved areas, and able to be produced for the high-volume testing required to return to normal, everyday activities.

“To date, COVID-19 was confirmed in over 100 million people and caused over 2 million fatalities worldwide,” Lucas said. “A rapid and accurate P.O.C. [point of care] diagnostic test for COVID-19 is critical to enable safe re-entry and long-term stability of an open society.”

Researchers envision their diagnostic test being used in a variety of places including clinical settings, government and private buildings, sporting events, concerts, schools, universities and more.

At the beginning of the pandemic, the team was not sure how to face the urgent and complex problem of COVID-19. Quickly, Patrick Halley, the research engineer for the team, came up with the idea to develop a SARS-CoV-2-biosensing DNA origami device.

“My depressed mood during the early days of the shutdown turned into focus and hope that we could contribute to help society through the days of the pandemic,” Lucas said.

Dr. Carlos Castro, principal investigator at the Nanoengineering and Biodesign Laboratory, was quick to support the researchers’ idea. Lucas said that Castro’s expertise in nanoengineering offered tremendous direction to their efforts to develop the technology as quickly as possible.

Castro also worked in the early stages of the pandemic to produce 3D printed face shields in March of 2020 that helped provide healthcare workers with PPE during equipment shortages

In the beginning, the research group started with one of the platforms they have been using in the lab for years and modified it toward COVID-19 detection, but faced many issues when they tested it with the COVID RNA sequence, according to Melika Shahhosseini, the MAE graduate student who has been folding and testing these variations since April.

They designed several different sensors and modified the test multiple times before finding the right fit.

Melika Shahhosseini

“Since then, we have changed this structure constantly and I have been folding each version, purifying it, and test it with RNA sequence,” Shahhosseini said.  “I can say that we finally have a platform that responds to the COVID-19 sequence target with no issue, and right now, I am testing the fluorescence response, storing and handling conditions to better prepare if as a product for the market.”

When the team started working on this project, they were the only people allowed to go to the lab and were constantly reminded "why" the world needed this rapid test and how they could make an impact right away.

“I could actually see how what I do impacts everything,” Shahhosseini said. “It was very practical and goal-oriented and I feel very lucky to be part of this project and learn along the process.”

The possibilities of this new test have the potential to go well beyond the current disease that is being faced on a global scale.

“Our COVID-19 biosensing device can be easily changed to detect other viral diseases like the flu and the coronavirus at the same time. Also, the device can be changed to keep up with the mutant variants of the coronavirus very quickly,” Lucas said. “We also anticipate that the device can be altered to serve as a cancer diagnostic screening device by detecting circulating tumor DNA from patient blood samples in the future.”

Because of the possibility for widespread impact, Lucas and Halley hope to deliver the Ohio State-designed test to the public. The researchers hope to launch a biotech startup company that will allow them to commercialize their technology, bringing it to the public much quicker than originally planned.

Category: Research