ELISA is an immunosorbent biochemical essay that is applied to quantify the substances present in body fluids. It involves the detection of large sized molecules instead of small molecules i.e. ions, glucose and potassium.
Elisa is applied to diagnose a large number of pathological conditions.
The basic step in this essay is immobilization of the antigen. During this essay, an antibody which specifically binds with a particular antigen is directed to bind with a specific antigen. After the formation of an antigen-antibody complex, a secondary antibody is added to the mixture to detect the primary antibody for a particular antigen.
The antibody is then linked to an enzyme by bioconjugation. At the last step, an enzymatic substrate is added which generates a clear single which measures the quantity of antigen in sample. ELISA is considered very dependable now a days for their consistency and rapid analysis.