Glucose monitor used to detect SARS-CoV-2 antibodies
Adapting glucose monitors/meters to sense other target molecules can be an inexpensive method for infectious disease detection. Researchers report on such a test in the Journal of the American Chemical Society, whereby a simple glucose-meter-based test incorporating a novel fusion protein accurately detected SARS-CoV-2 antibodies and allowed users to monitor antibody levels at-home, over a period of time.
Immune protection can be determined through a person’s level of SARS-CoV-2 antibodies, but the gold standard measurement – the enzyme-linked immunosorbent assay (ELISA) – requires expensive equipment and specialised technicians.
Researchers wanted to test if glucose meters could be an alternative detection device this purpose.
Dr. Netzahualcóyotl Arroyo Currás, Assistant Professor of Pharmacology and Molecular Sciences at Johns Hopkins University School of Medicine, and colleagues, wanted to see whether producing a fusion protein consisting of the enzyme invertase and a detection antibody would work to allow SARS-CoV-2 antibody levels to be read with a glucose meter.
The small devices would be able to detect antibodies or other molecules through glucose production: for example, if a detection antibody in the test binds to an antibody in a patient’s blood, then a reaction occurs that produces glucose, which the device can easily detect.
The researchers showed that the fusion protein bound to human immunoglobin (IgG) and successfully produced glucose from sucrose, which was detectable by a glucose meter. The researchers also found this method to work as well as four different ELISAs, and concluded that it can be adapted to test for SARS-CoV-2 variants and other infectious diseases.