Sensor Rapidly Detects SARS-CoV-2, Antibodies, and Inflammatory Markers

Researchers at Caltech have developed a low-cost multiplex test that can rapidly provide three different types of data on COVID-19.

The test can detect the presence of SARS-CoV-2, antibodies against the virus (potentially indicating a level of immunity), and inflammatory markers that could indicate the severity of COVID-19. Using blood or saliva, the test can provide a result in as little as 10 minutes. The researchers hope that it could soon be used by people at home to assess their COVID-19 status.

Testing is a cornerstone in the fight against COVID-19, whether the test is to determine whether the virus is present, or to see whether someone may have immunity to it. However, testing supplies have been stretched in many countries, and getting access to a timely test can be challenging. Having easy-to-use tests that provide an immediate answer at home could help with the situation.

This challenge inspired researchers at Caltech to develop a new test that could potentially be used at home. Their new device can provide three different types of data for those worried that they may have COVID-19, or for those who wish to see whether they had it in the past.

Containing a porous graphene layer with a large surface area, the team’s sensor is highly sensitive to small amounts of the target molecules, meaning that a saliva or blood sample is sufficient, and it is not necessary to undergo invasive swabbing. Antibodies and proteins attached to the graphene layer can bind SARS-CoV-2, along with antibodies against SARS-CoV-2 and inflammatory markers that are present in the tested sample.

“This is the only telemedicine platform I’ve seen that can give information about the infection in three types of data with a single sensor,” said Wei Gao, a researcher involved in the study. “In as little as a few minutes, we can simultaneously check these levels, so we get a full picture about the infection, including early infection, immunity, and severity.”

So far, the device has been tested in a small number of volunteers and the early results are promising. The researchers hope to conduct larger studies soon to confirm that the test can give accurate and reliable results.

“Our ultimate aim really is home use,” said Gao. “In the following year, we plan to mail them to high-risk individuals for at-home testing. And in the future, this platform could be modified for other types of infectious disease testing at home.”