Science & Enterprise subscription

Follow us on Twitter

  • Voice telephone, who knew? ... Why the Phone Is Key to Getting Covid Shots in Arms https://t.co/zf0KWGX7Ca
    about 54 mins ago
  • Israel is emerging as the world's leader in vaccinating its population, and seeing results in declines of new Covid… https://t.co/FBswRzZQld
    about 5 hours ago
  • New post on Science and Enterprise: Infographic – Israel Halts Covid-19 Spread with Vaccines https://t.co/ezP927woim #Science #Business
    about 5 hours ago
  • We wrote about this project last July. Read about it first on Science & Enterprise. ... Researchers Are Hatching a… https://t.co/rujRcnlZax
    about 9 hours ago
  • A biotechnology company using protein dynamics to develop precision cancer therapies is acquiring a drug discovery… https://t.co/AzEb3ERy5f
    about 24 hours ago

Please share Science & Enterprise

Univ Building Single Covid-19 Diagnostic, Antibody Test

D4 test slide

Prototype D4 test slide (Duke University)

28 Apr. 2020. A university bio-engineering lab is developing a single point-of-care test that detects both Covid-19 viruses in nasal swabs and antibodies in blood samples. The one-year project at Duke University in Durham, North Carolina  is funded by a $119,337 grant, awarded last week from National Science Foundation.

A team from the lab of biomedical engineering and materials science professor Ashutosh Chilkoti is adapting recent work in developing a fast, sensitive, and inexpensive test that detects pathogens at the point of care, rather than sending specimens to a remote lab for analysis. Chilkoti’s group studies bio-active peptide polymers and interactions between biological molecules and polymer chemistry to design sensitive interfaces like those for diagnosing diseases.

The lab, as reported by Science & Enterprise in August 2017, published its D4 assay, a microfluidics or lab-on-a-chip device about the size of a microscope slide that returns results similar to the enzyme-linked immunosorbent assay or ELISA test. That test, a diagnostic lab mainstay, identifies and measures the number of antigens — proteins triggering an immune response by antibodies — in blood samples. ELISA is a sensitive technology that tests for a number of different conditions, but it uses stationary desktop or larger equipment, needs trained technicians or robotics to expertly handle blood samples, and can take as long as a day to return results.

To provide a faster, simpler, and less expensive technology than ELISA, the researchers devised a solution with antibodies formulated into nanoscale polymer brushes on glass slides. The nanoscale brushes are applied with inkjet printing on a non-stick polymer surface, to prevent fouling the slide’s surface. The non-stick feature is important, since it enables the D4 assay to detect low levels of antigens in samples as small as a few drops of blood. In addition, colleagues at UCLA devised a 3-D printed smartphone attachment to capture and interpret chemical reactions on the slide.

The new project adapts the D4 technology for capturing antigens in a few drops of blood indicating protective antibodies for SARS-CoV-2 viruses responsible for Covid-19 infections. The D4 assay in this case looks specifically for antigens invoked by S1 spike proteins characteristic of SARS-CoV-2 viruses. In addition, the test slide has detection antibodies with fluorescent markers that bind to nucleocapsid proteins, another characteristic SARS-CoV-2 identifier, in nasal swabs and light up for detection. A handheld wireless detector called the D4Scope captures and interprets reactions on the slide in about 30 minutes, then transmits the results to a remote server.

The researchers say the D4 assay already detected a synthetic SARS-CoV-2 virus indicator in lab tests. “We’ve shown a proof-of-concept,” says Chilkoti in a university statement, “by detecting a biomarker of the SARS-CoV-2 virus, which causes Covid-19, and the next step would be to validate this with patient samples. Our test is designed to be truly point-of-care, and this pandemic is clearly a scenario when a portable, fast, and cost-effective diagnostic would be most useful.”

National Science Foundation awarded the funds under its Rapid Response Research program that provides up to $200,000 for projects of up to one year. While this project has a one-year deadline, Chilkoti expects to begin testing the D4 assay with patients in a few months.

More from Science & Enterprise:

*     *     *

4 comments to Univ Building Single Covid-19 Diagnostic, Antibody Test