Fig. 1

Scheme of SARS-CoV-2 variants array on pGOLD for IgG/IgM profiling. a Wild-type, Alpha, Beta, Delta, Omicron variants of epitope of the spike protein (S1) as well as a mixture of recombinant human IgG and IgM as the positive reference were arrayed on the pGOLD substrate. The secondary antibodies labeled with IRDye800 and Cy5 were bound to the primary antibody IgG, IgM after they were specifically bound to the antigens. The chips were imaged by the scanner with 785 nm channel for IgG detection and 670 nm channel for IgM detection. The positive reference in each block served as inter-block signal normalization. b The detailed information of S1 mutation sites of different variants in this study