ELISA or Enzyme-Linked Immunosorbent Assay is a molecular biology technique which is used to detect the presence of an antigen in a biological sample.
ELISA often utilizes two antibodies, one of which is specific to the antigen and the other of which is coupled to an enzyme. It is often called a Sandwich Assay, due to the use of the two antibodies, which "sandwich" the antigen in between them.
