What is ELISA method of Blood Testing?

ELISA means ENZYME LINKED IMMUNOSORBENT ASSAY.

ELISA is an immunological technique which is used to detect the presence of an antibody or an antigen in a sample. A known amount of antigen is coated on a solid phase like that in the well of a polystyrene microtiter plate and sample containing specific antibodies is added in the wells to allow antigen-antibody binding. The immune complex thus formed is linked to an enzyme, which acts on a substrate to give a coloured reaction which is detected using ultramodern ELISA plate readers. Since ELISA technique utilizes enzyme labels to produce detectable signals, it is given the name Enzyme-Linked Immunosorbent Assay.