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enzyme-linked immunosorbent assayZoomA-Z

Subject - Biochemistry

Enzyme-linked immunosorbent assay (ELISA) is a method for determining the concentrations of antigens or antibodies. The method is based on the principle that the substance being detected (e.g. an antigen) binds to a solid surface covered with a specific antibody and becomes concentrated there. A second antibody marked with an enzyme that can be used for colorimetric detection is then added. Usually, this enzyme is alkaline phosphatase or peroxidase. Detection of the corresponding colour makes it possible to determine the concentration of the substance being tested; even very small amounts can be detected.

Radioimmunoassay (RIA) is a similar technique in which the detection reagent has a radioactive marker. Quantification is then possible through measurement of the radiation.

Fig.1
ELISA Movie (german)
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