Sandwich ELISA

Written by Administrator

Monday, 23 June 2008

Learn about the sandwich ELISA assay.

Sandwich ELISA

Sandwich ELISA is a modification of the ELISA assay, it is also known as antigen-capture assay. This modification of ELISA is used to detect secreted products such as cytokines. The marked difference between this technique and the general ELISA technique is that rather than the antigen being directly attached to a plastic plate, antigen-specific antibodies are bound to the plate. These antibodies are able to bind antigen with high affinity and therefore concentrate the antigen on the surface of the plate. This is also the case when antigens are present in very low concentrations in the initial mixture. In the final steps a separate labelled antibody which recognizes a different epitope to the immobilized first antibody is then used to detect the bound antigen.