Enzyme linked immunosorbent assay (ELISA)

Abstract

Enzyme-Linked Immunosorbent Assay (ELISA) is a common analytical biochemistry immunoassay, first described in1972 by Engvall and Perlmann. The assay is useful for the detection of antibodies, peptides, proteins, and small molecules using a multi-well plate. This assay is the preferred method to determine the titer of antisera and purified antibodies. ELISA can also be successfully employed for the quantitative assessment of an antigen in a sample, often available in convenient, easy-to-use kit formats. ELISA is used as a diagnostic tool in medicine, plant pathology, and biotechnology as well as for the quality control check in industries. In an ELISA, an antigen must be immobilized on a solid surface and then complexed with an antibody that is linked to an enzyme. Detection is accomplished by assessing the conjugated enzyme activity via incubation with a substrate to produce a measurable product. The most crucial element of the detection strategy is a highly specific antibody-antigen interaction. In this chapter we will discuss the history, procedure, different types of ELISA and the applications.