The eRapid Sensor for COVID-19, shown here in a composite image with a quarter for scale, uses a novel microfluidic design to mix and transport samples and reagents to produce an electrical readout that indicates the presence of viral RNA, antibodies, or both, in a person’s saliva. Image: Wyss Institute at Harvard University
This article is part of Harvard Medical School’s continuing coverage of COVID-19.
As the COVID-19 pandemic runs its course, the questions we ask ourselves have evolved, from how do I know if I’m infected to how strong is my immunity to which strain of the virus do I have. As new variants continue to emerge, it’s likely that we’ll keep asking ourselves those questions, often at the same time.
A new diagnostic device in development could offer a way to get answers to all of them in a couple of hours without needing to send samples to a lab.
The prototype point-of-care device, created by members of the Wyss Institute for Biologically Inspired Engineering at Harvard University, combines the institute’s eRapid and SHERLOCK technologies into a single, postcard-sized system that can simultaneously detect the presence of both SARS-CoV-2 RNA and antibodies against the virus in a patient’s saliva, potentially along with multiple other biomarkers.
The protoype is described in Nature Biomedical Engineering.
“This diagnostic can enable cheaper, multiplexed monitoring of infection and immunity in populations over time, at levels of accuracy that are comparable to expensive lab tests,” said co-first author Devora Najjar, a graduate student at the MIT Media Lab and the Wyss Institute. “Such an approach could dramatically improve the global response to future pandemics and also provide insight into which treatment individuals should receive.”
As a prototype, the device is still a preliminary model and is not yet ready for large-scale manufacturing and distribution.
So far, however, signs are promising. The prototype was made at low cost, has a compact and user-friendly design, and minimizes the number of steps patients would need to perform, reducing the possibility of user error, the authors said. They propose that customized cartridges could be easily manufactured to detect antigens and antibodies from different diseases and could be fit into a reusable housing and readout device that users would keep in their homes.
The device was born from a collaboration between the labs of Wyss Institute core faculty members and co-senior authors Jim Collins and Don Ingber, who is also the institute’s founding director.
“In the early days [of the pandemic], everyone was working on developing diagnostics that could detect either SARS-CoV-2 or antibodies against it, but not both,” said co-first author Helena de Puig, a postdoctoral fellow at the Wyss Institute. “We knew that we could successfully detect the presence of DNA and RNA molecules electrochemically, thanks to our work on Lyme disease. We decided to figure out how to multiplex that with antibody detection in order to create an all-in-one test to help track infections and fight the pandemic.”
“Currently, there is a lack of low-cost diagnostic platforms that can enable accurate detection of multiple classes of molecules without requiring a trip to a lab,” said co-first author Pawan Jolly, a senior staff scientist at the Wyss Institute. “Our system offers the best of both worlds—high accuracy and low cost in a multiplexed platform—and could provide a lot of value to both patients and clinicians at the point of care.”
“I’m very proud of these teams for coming together during a global crisis that ground most activity to a halt and creating something new and useful that offers great promise for point-of-care diagnosis and management of a broad range of diseases around the world,” said co-senior author Ingber, who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Boston Children’s Hospital, as well as the Hansjörg Wyss Professor of Bioinspired Engineering at the Harvard John A. Paulson School of Engineering and Applied Sciences.
Collins is a co-founder of Sherlock Biosciences, which is developing the SHERLOCK technology into diagnostics for COVID-19 and other diseases.
This research was supported by the Wyss Institute for Biologically Inspired Engineering at Harvard University, the Paul G. Allen Frontiers Group, the UK Natural Environment Research Council (NERC) GW4 FRESH CDT, the Fonds de recherche du Québec nature et technologie, Ms. Enid Schwartz, the Mark and Lisa Schwartz Foundation, the Massachusetts Consortium for Pathogen Readiness, the Ragon Institute of MGH, MIT and Harvard, and the Harvard University Center for AIDS Research.
Read the full story on the Wyss website.
Adapted from a Wyss Institute news release.
