What Is a Direct Elisa

First described by Engvall and Perlmann, the enzyme-linked immunosorbent assay (ELISA) is a rapid and sensitive method for detection and quantitation of an antigen using an enzyme-labeled antibody. … Direct ELISA is the simplest format requiring an antigen and an enzyme-conjugated antibody specific to the antigen.

What is a direct and indirect ELISA?

These assays differ only in the detection antibody used. In a direct elisa only one antibody is used—this single antibody is conjugated directly to the detection enzyme. The indirect elisa requires two antibodies—a primary antibody and an enzyme-linked secondary antibody that is complementary to the primary antibody.

Why it is called direct ELISA?

The procedure for a sandwich ELISA firstly requires the well of an ELISA plate to be coated with a capture antibody. The analyte or sample is then added, followed by a detection antibody. The detection antibody can be enzyme conjugated, in which case this is referred to as a direct sandwich ELISA.