Imaging Platform Could Deliver Specific, Reliable COVID-19 Antibody Testing

A robust, low-cost imaging platform using lab-on-a-chip technology, created by University of California, Irvine (UCI) scientists, could be available for rapid coronavirus diagnostic and antibody testing by the end of 2020. The 3D-printable, portable imager detects antibodies in the blood against SARS-CoV-2 in a highly sensitive and specific manner, according to the UCI team.

Using blood from a finger prick, the UCI test probes hundreds of antibody responses to 14 respiratory viruses, including SARS-CoV-2, in two to four hours. The results are printed on a low-cost imaging platform. The same device can also process the results of commonly used nose swab tests for SARS-CoV-2 so that patients can be tested for COVID-19 and its antibodies on a single platform.

Called the TinyArray imager, the device combines a 3D-printed prototype with an off-the-shelf LED and a small 5-MP camera to find markers for many antibodies simultaneously. According to the researchers, this setup ensures accuracy equal to that of expensive imaging systems while making the platform portable enough to deploy anywhere, at a cost of only $200. To evaluate the device, the team probed and imaged coronavirus microarrays with COVID-19 positive and negative sera and achieved a performance on par with a commercial microarray reader 100× more expensive than the TinyArray imager.

Systems that test for the full range of antibodies necessary for reliable results from COVID-19 testing require imaging machines that cost $10,000 to $100,000 and are too bulky for widespread use, the researchers said. Areas without the resources to acquire one of these machines must send their samples to external labs for testing, meaning that results take days instead of hours.

The UCI team has already completed 5000 tests in Orange County, Calif., and its goal is to test 20,000 samples per unit a day. The researchers are partnering with UCI startups Velox Biosystems Inc. and Nanommune Inc. to scale up production. They expect that the TinyArray imager will be ready to deploy across the U.S. by the end of 2020 and are working with scientists in Uruguay, Russia, and Thailand to develop similar systems for their nations.

“This would be great for a low-income country,” researcher Per Niklas Hedde said. “Because the device’s materials are cheap and easy to obtain, the platform is easy to manufacture and use in low-resource areas, making testing accessible on a world scale.”

The research was published in Lab on a Chip (www.doi.org/10.1039/D0LC00547A).