For the best experience on the Abcam website please upgrade to a modern browser such as Google Chrome
Choose from our wide range of ELISA kits to detect or quantitate one or more specific proteins in a solution or biological sample.
Figure 1. Different ELISA formats.
In a sandwich ELISA assay, an immobilized capture antibody pre-coated onto a 96-well plate binds to the target protein and captures it from a liquid sample.
Detection antibodies are then added to create complexes where the detection antibodies also bind to the captured target protein, catalyze the appearance of a colored or fluorescent product through the action of a covalently linked enzyme.
The amount of color produced is proportional to the amount of target protein in the sample. A sandwich ELISA can be:
SimpleStep ELISA Kits
Our brand of ELISA kits provide improved speed and performance while retaining the familiar process and standard data output of a traditional ELISA kit.
SimpleStep ELISA kits reduce the number of wash steps from 9 (3x3) to 3 (1x3) by enabling complex formation in one step rather than sequentially. Total time required is less than two hours.
We also offer ELISA sets with validated antibody pairs and standards for those wanting to develop their own ELISA method.
In a competitive ELISA, sample antigen and labeled antigen compete for capture antibody binding. The more target protein there is in the sample, the less labeled antigen will be captured and the weaker the signal.
In an indirect ELISA, the target protein adheres to the bottom of a 96-well plate, a primary antibody binds to the target, and a labeled secondary antibody binds to the primary for detection. The method can also be used to detect specific antibodies in a serum sample by substituting the serum for the primary antibody.
The main advantage of an indirect ELISA is that one labeled secondary antibody can be used with many different primary antibodies.