Question

question 39
2 points
what kind of elisa assay is shown in the diagram?
a indirect
b sandwich
c direct

Explanation:

To determine the ELISA assay type, we analyze the diagram:

• Indirect ELISA uses a primary antibody to bind the antigen, then a secondary antibody (conjugated to an enzyme) that binds to the primary antibody. The diagram shows a primary antibody (binding to the antigen) and a secondary antibody conjugate (with enzyme \( E \)) binding to the primary antibody, matching indirect ELISA.
• Sandwich ELISA has the antigen "sandwiched" between two antibodies (capture and detection), which is not the case here.
• Direct ELISA uses a single antibody (conjugated to enzyme) binding directly to the antigen, which does not match the two - antibody (primary and secondary) setup here.

Answer:

A. Indirect