Since 1971 ELISA is used for detection and or determining the concentration of proteins within analyte mixture, low molecular weight compounds (e.g. Toxins, hormones) or viruses.
The ELISA is based on an antibody-antigen detection. Basis of this is the immobilization of an antigen or antibody on a multiwell plate (e.g. Polystyrene). The analyte is bound in the subsequent step.
The antigens are bound by the antibodies via hydrogen bonds, ionic and hydrophobic interactions, and Van-der-Waals forces. This binding occurs on a key-lock principle and is very specific. The antibodies used can thereby be monoclonal (mAb) or polyclonal (pAb). Monoclonal antibodies are made from hybridoma cells, a fusion of a cancer cell (myeloma) and an antibody-producing cell (B-cell) which selectively bind a specific epitope on the antigen. Polyclonal antibodies are a mixture of different antibodies which recognize different epitopes on the surface of one antigen. Once successfully attached the detection is normally made by colorimetry.
The successful antigen-antibody binding and addition of a substrate leads to a color change in the microtiter plate, which is catalyzed by an enzyme that has been previously conjugated to the antibody or antigen.
For further information, please refer to our Data Library at any time.