Magnetic bead-based ELISA allow inexpensive, rapid and quantitative detection of human antibodies against SARS-CoV-2

Here we describe a novel immunogenic method to detect COVID-19. The method is a chromogenic magnetic bead-based ELISA which allows inexpensive and quantitative detection of human IgG or IgM antibodies against SARS-CoV-2 in serum or whole blood samples in just 12 minutes. As a proof of concept, we compared the performance of our new method to classical ELISA. Person correlation between optical densities obtained using the two methods was 0.98, the color intensity observed in the novel method correlated with antibody titers determined by classical ELISA. The novel magnetic bead-based ELISA correctly classified all 6 positive COVID-19 samples tested and showed 100% specificity as judged by the analysis of a cohort of 26 negative samples. The magnetic bead-based ELISA performed better than classic ELISA to discriminate COVID-19 positive serum with low antibody titer. The chromogenic magnetic bead-based ELISA method described here can be applied to both point of care and high throughput analysis. The method is readily adaptable to be used with other protein and peptide-based antigens.