Engineers at the McKelvey School of Engineering at Washington University in St. Louis have received federal funding for a rapid COVID-19 test using a newly developed technology.
Srikanth Singamaneni, professor of mechanical engineering and materials science, and his team have developed a rapid, highly sensitive and accurate biosensor based on an ultrabright fluorescent nanoprobe, which has the potential to be broadly deployed.
Called plasmonic-fluor, the ultrabright fluorescent nanoprobe can also help in resource-limited conditions because it requires fewer complex instruments to read the results. The National Science Foundation has awarded Singamaneni and his team a $100,008 grant toward developing a COVID-19 test using plasmonic-fluor.
Singamaneni hypothesizes their plasmonic-fluor-based biosensor will be 100 times more sensitive compared with the conventional SARS-CoV-2 antibody detection method. Increased sensitivity would allow clinicians and researchers to more easily find positive cases and lessen the chance of false negatives.
Plasmonic-fluor works by increasing the fluorescence signal to background noise. Imagine trying to catch fireflies outside on a sunny day. You might net one or two, but against the glare of the sun, those little buggers are difficult to see. What if those fireflies had the similar brightness as a high-powered flashlight?
Plasmonic-fluor effectively turns up the brightness of fluorescent labels used in a variety of biosensing and bioimaging methods. In addition to COVID-19 testing, it could potentially be used to diagnose, for instance, that a person has had a heart attack by measuring the levels of relevant molecules in blood or urine samples.
Using plasmonic-fluor, which is composed of gold nanoparticles coated with conventional dyes, researchers have been able to achieve up to a 6,700-fold brighter fluorescent nanolabel compared with conventional dyes, which can potentially lead to early diagnosis. Using this nanolabel as an ultrabright flashlight, they have demonstrated the detection of extremely small amounts of target biomolecules in biofluids and even molecules present on the cells.
The study was published in the April 20, 2020, issue of Nature Biomedical Engineering.