ELISA

A very sensitive method that can be used to detect certain molecules (proteins)

ELISA (enzyme-linked immunosorbent assay) is now a widespread method for detecting individual proteins. It makes use of the mechanisms of the immune system. If the immune system recognises a substance as being foreign, it produces antibodies that attach themselves to the foreign molecule, thereby marking it.

This anitbody-antigen reaction is used in the ELISA test. If researchers want to detect a particular protein, they first need to know the relevant antibody and produce it using various genetic or cell biology methods. If the protein in question is present in a sample, the antibodies applied to a carrier medium will fish it out. This triggers an enzyme-controlled reaction, which leads to a visible colour deposit.

Today, ELISA tests are widespread in medical diagnosis. But they are also used in a wide range of other areas where individual proteins need to be detected. They are not to be confused with methods for detecting DNA or DNA sequences.