There is no way to reliably detect whether someone’s driving is impaired by marijuana, so a team of researchers at Pitt and UPMC, led by Dr. Alexander Star, invented a marijuana breathalyzer.

Now, that team is using that same technology to fight the Covid crisis.

Along with Pitt Assistant Professor of Pathology Dr. Sarah Wheeler and Dr. Michael R. Shurin — who were developing a rapid test for HIV — the team is working on a handheld device that will detect Covid electronically in five minutes. Faster and more accurate than conventional Covid tests, the device can be used virtually anywhere.

The project is still in its early stages. But what the team has, so far, is a very tiny, all-important chip, one so tiny it’s dwarfed by Abe’s head on the face of a penny.

The sensor chip on a penny. Photo courtesy of UPMC.

The chip uses a highly sensitive array of carbon fibers, 100,000 times smaller than a human hair, with SARS-CoV-2 antibodies stitched onto them. When the virus reaches the antibodies, they change the electrical current of the carbon fibers, allowing for a quick positive reading.

“You can imagine that if just even a few viral proteins bind on the antibodies on the surface of those tiny, tiny wires that we have in our chips, we can get this real-time electronic detection, with improved speed and accuracy,” says Star.

The marijuana breathalyzer detects THC, the main psychoactive compound found in marijuana, so it made sense to approach the attack on Covid in a similar fashion — although the handheld device will require a nasal swab (you won’t breathe into it).

Speed is paramount when it comes to Covid.

“Much like HIV, Covid is spread without people knowing they have it, for the most part,” says Wheeler.

“These are the kinds of tests that people could do at home or remotely rather than having to go into a hospital setting. So people would be able to tell earlier if they’re contagious.”

When people know they have the virus, they know to stay home and stop the spread.

There are other advantages to this project, should it reach production.

“Basically, these sensor chips feature a small size and low manufacturing cost and low power consumption,” says Star. “So that’s what makes it a good technology platform for all kinds of sensors.

“Carbon nanotubes are really, really inexpensive,” he adds.

Dr. Star with the marijuana breathalyzer. Photo by Tom Altany.

The project was just published in the American Chemical Society (ACS Publications) journal. The research was originally funded by $100,000 from the Pitt Innovation Challenge through the university’s Clinical and Translational Science Institute.