Enzyme-linked Immunosorbent Assay (ELISA)

- capture Abs (antibodies) to capture the target Ag (antigens) - enzyme labeled Abs used to detect target Ag (ex. horseradish peroxidase, alkaline phosphatase, β-galactosidase) - highly specific and sensitive immunological tool - colored product made when substrate is added - amt of product is proportional to the amount of antigen present