New Device Rapidly Detects Viruses Like COVID-19

Researchers say the device can tell if someone has a virus with 95% percent accuracy, a significant improvement over current rapid tests.

Researchers at the University of Central Florida have developed a device that detects viruses such as COVID-19 in the body as quickly and more accurately than today’s widely used rapid-detection tests.

The optical sensor uses nanotechnology to accurately identify viruses within seconds from blood samples. Researchers say the device can tell if someone has a virus with 95% percent accuracy, a significant improvement over current rapid tests that experts warn may have low accuracy. Testing for viruses is important for early treatment and to prevent their spread.

The results are detailed in a new study in the journal Nano Letters.

The researchers tested the device with samples of the Dengue virus, a mosquito-borne pathogen that causes Dengue fever and poses a threat to people in the tropics. However, the technology could easily be adapted to detect other viruses, such as COVID-19, said study co-author Debashis Chanda, a professor in UCF’s NanoScience Technology Center.

Debashis Chanda, a professor in UCF’s NanoScience Technology Center and co-author of the study, demonstrates the optical chip for virus detection. Credit: University of Central Florida

“The sensitive optical sensor, along with the rapid fabrication approach used in this work, promises to translate this promising technology to any virus detection, including COVID-19 and its mutations, with a high degree of specificity and accuracy,” Chanda said. “Here we demonstrated a credible technique that combines PCR-like genetic coding and optics on a chip for accurate virus detection directly from blood.”

The device closely matches the accuracy of the gold standard PCR-based tests, but with nearly instant results rather than results that take several days to receive. Accuracy is also a significant improvement over current rapid antigen tests, which the US Food and Drug Administration and the US Centers for Disease Control have warned can produce inaccurate results if viral loads are low or test instructions are not followed correctly.

The device works by using nanoscale gold patterns that mirror the signature of the virus it is supposed to detect in a blood sample. Different viruses can be detected by using different DNA sequences that selectively target specific viruses.

The key to the device’s performance is that it can detect viruses directly from blood samples without the need for sample preparation or purification, speeding up the test and improving accuracy.

“A vast majority of biosensor demonstrations in the literature use buffer solutions as the test matrix to contain the target analyte,” Chanda says. “However, these approaches are not practical in real life applications because complex biological fluids, such as blood, containing the targeted biomarkers are the main source for detection and at the same time the main source of protein contamination leading to sensor failure.”

The researchers confirmed the effectiveness of the device with multiple tests using different virus concentration levels and solution environments, including those with the presence of non-target virus biomarkers.

Abraham Vazquez-Guardado, the study’s lead author and a postdoctoral researcher at Northwestern University who worked on the study as a doctoral student in Chanda’s lab, says he’s excited about its potential.

“While there have been previous optical biosensing demonstrations in human serum, they still require an offline complex and dedicated sample preparation performed by skilled personnel — a commodity not available in typical point-of-care applications,” says Vazquez-Guardado . “This work demonstrated for the first time an integrated device that separated plasma from the blood and detect the target virus without any preprocessing with potential for practical use in the near future.”

Chanda says the next steps for the investigation are to customize the device to detect more viruses.

Reference: “DNA-modified plasmonic sensor for the direct detection of virus biomarkers from the blood” by Abraham Vázquez-Guardado, Freya Mehta, Beatriz Jimenez, Aritra Biswas, Keval Ray, Aliyah Baksh, Sang Lee, Nileshi Saraf, Sudipta Seal and Debashis Chanda , September 8, 2021, Nanoletters.
DOI: 10.1021/acs.nanolet.1c01609

Study co-authors are Freya Mehta, Beatriz Jimenez, Keval Ray, Aliyah Baksh – undergraduate students at the NanoScience Technology Center; Aritra Biswas ’21MS — a doctoral student at UCF’s College of Optics and Photonics; Sang Lee ’16 — a master’s student at the NanoScience Technology Center; Nileshi Saraf — graduate of UCF’s Department of Material Science and Engineering doctoral program; and Professor Sudipta Seal — chair of UCF’s Department of Material Science and Engineering.

Chanda holds a joint appointment in UCF’s Department of NanoScience Technology Center, the Department of Physics and the College of Optics and Photonics. He received his PhD in photonics from the University of Toronto and worked as a postdoctoral researcher at the University of Illinois at Urbana-Champaign before joining UCF in 2012.

The research was supported in part by the National Science Foundation and UCF’s COVID-19 Artificial Intelligence and Big Data Initiative program.