This new ‘lab-on-a-chip’ antibody test may revolutionize COVID-19 detection

A COVID-19 test that’s affordable, quick, portable, and highly accurate may soon be a reality thanks to a team of researchers at the University of Michigan. Providing coronavirus tests for all in need has been one of the biggest challenges of this global pandemic, but this new COVID-19 antibody test has the potential to change all of that.

So what separates this test from the rest? Most of the process is localized to a single “lab on a chip,” combining multiple lab functions within a single device. As if all that wasn’t impressive enough, the chip is just a few millimeters or centimeters in size.

A superior antibody test is badly needed in the US, and this new chip separates itself from the pack thanks to the fact that it’s much smaller, more detailed, and doesn’t rely solely on chemical mixtures or substances.

While this new test was invented at the University of Michigan, it was developed by a UM startup called Optofluidic Bioassay.

“We are unique because we are a hardware company,” says Xudong (Sherman) Fan, U-M biomedical engineering professor and co-founder of Optofluidic Bioassay, in a news release. “Anyone working on COVID-19 antibody tests can use their reagents in our device.”

This new invention is believed to be the first-ever “microfluidic” (lab on a chip) approach to ELISA (enzyme-linked immunosorbent assay) antibody testing. It’s also much faster than any other ELISA antibody test.

Other ELISA tests require machines the size of refrigerators and take several hours to produce a result. This chip gives a quantitative (number of antibodies) and accurate reading within 15 minutes! All it needs is a small sample of blood, then, a machine about the size of a microwave is used to test multiple samples simultaneously.

Researchers are currently in the process of validating the chip for COVID-19 antibody testing; it has already successfully detected synthetic COVID-19 antibodies. So, as a next step, it’s currently being used at an undisclosed hospital in New Jersey for tests involving blood samples taken from legitimate COVID-19 patients.

“Our approach offers the best of both worlds. We can achieve the quickness and simplicity of the rapid diagnostic test with the accuracy of the standard ELISA quantitative measure,” Fan comments. 

Most coronavirus testing is currently being performed via reverse transcriptase-polymerase chain reaction (RT-PCR) tests. These tests, however, are only capable of detecting an active coronavirus infection and have been known to produce false-negative results far too often. Antibody tests, on the other hand, tell a much larger story. These tests can also identify people who have been exposed to the coronavirus and developed immunity, at least temporarily. 

If this new chip antibody test can indeed be approved and mass-produced, it would be an enormous asset to health officials and governments as they attempt to understand the true extent of the spread of COVID-19 and its death rate. Moreover, the research team at UM says their test can also provide doctors with rapid and near real-time data on how coronavirus patients are responding to certain treatments, and even a vaccine once one has been developed and approved.

“Because our device generates such sensitive and quantitative measurements, we believe its use goes beyond identifying recovered patients. Antibodies begin to show up a few days after infection, so we could use this approach to monitor patients’ immune response to infection, treatment, and vaccination,” Fan explains.

The few preliminary antibody testing projects being carried out in the United States have already yielded significant results. Just the first round of antibody testing in Los Angeles earlier this month revealed that an estimated 4.1% of the county’s adult population had been in contact with the virus. That’s a whole lot more people than had tested positive in LA via PCR tests. 

The coronavirus has been spreading from person to person largely undetected. This new form of antibody testing could change that.

Another key element in all of this is cost. Almost unbelievably, the chip is quite reasonable when it comes to price.

“The estimated cost of testing is a few dollars per test of two to three different antibodies, making this a very viable option for use in hospitals, doctors’ offices, field clinics and potentially even pharmacies,” adds Xiaotian Tan, a doctoral student in biomedical engineering who is collaborating on this project with Fan.