The serum ELISA test is based on the interaction between which of the following components?

• A. DNA and RNA
• B. Protein and lipid
• C. Enzyme and substrate
• D. Antigen and antibody

Answer: (D)

Verified step by step guidance

1. Understand that ELISA (Enzyme-Linked Immunosorbent Assay) is a biochemical technique used primarily to detect the presence of an antigen or antibody in a sample.
2. Recall that the fundamental principle of ELISA involves the specific binding interaction between an antigen and its corresponding antibody.
3. Recognize that in the ELISA test, either the antigen or the antibody is immobilized on a solid surface, and the complementary antibody or antigen is added to bind specifically to it.
4. Note that an enzyme-linked secondary antibody is then introduced, which binds to the antigen-antibody complex, allowing for a detectable signal (usually color change) upon addition of a substrate.
5. Conclude that the key components interacting in the serum ELISA test are the antigen and antibody, which provide the specificity and sensitivity of the assay.