Human Complement C4 ELISA Kit (Urine, Milk, Saliva, and Cell Culture Samples)The Human Complement C4 ELISA (Enzyme-Linked Immunosorbent Assay) kit is designed for detection of human complement C4 in urine, milk, saliva, CSF, and cell culture supernatants. This assay employs a quantitative sandwich enzyme immunoassay technique that measures human complement C4 in less than 4 hours. A polyclonal antibody specific for human complement C4 has been pre-coated onto a 96-well microplate with removable strips. Complement C4 in standards and samples is sandwiched by the immobilized antibody and biotinylated polyclonal antibody specific for complement C4, which is recognized by a streptavidin-peroxidase conjugate. All unbound material is then washed away and a peroxidase enzyme substrate is added. The color development is stopped and the intensity of the color is measured.