KE30002 is a qualitative measurement of Anti-SARS-CoV-2 protein human IgM for 2019-nCoV N protein in serum and plasma. The principle of the kit is indirect ELISA. Nucleocapsid Recombinant Protein has been pre-coated onto microplate well. The samples are added to the well, after incubation the wells are washed and a horseradish peroxidase conjugated anti-Human IgM is added to each well. Producing an complex " Recombinant Protein-human anti-N protein IgM antibody-HRP conjugated second antibody" . after incubation the wells are washed, followed by Tetramethyl-benzidine (TMB) reagent. Solution containing sulfuric acid is used to stop color development and the color intensity which is proportional to the quantity of bound protein is measurable at 450nm with the correction wavelength set at 630 nm.