D4 Cassette (IMAGE) Duke University Caption This point-of-care device uses the physics of fluids to draw a few drops of blood and biomedical lubricant through its components to test for COVID-19 antibodies and biomarkers without the need of any electricity. Credit Jake Heggestad Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.