Since the very first use of antibodies for the detection of antigens, many different technologies have been developed that make use of the antibodies' capability to bind to other molecules. In the 1950s, scientists Yalow and Berson developed a method that uses radioactivity to determine the amount of analyte in solution.
This so-called "radioimmunoassay" (RIA), for which Yarlow was awarded the Nobel Prize in 1977, is a very sensitive method for detecting hormones, but using radioactivity to detect antigens is unsafe and suitable for general use. There are also many companies available that provide ELISA kits. You can also check out the Human ADA/Adenosine Deaminase ELISA Kit PicoKine online.
Therefore, an alternative method was developed in which the enzyme binds to the antibody instead of the radioactive molecule and the molecule attaches to the surface. One of the most common applications today is the measurement of the number of biomolecules in a sample by "Enzyme-Linked Immunosorbent Assay" (ELISA).
The term originally referred to the use of enzymes to report interactions between antibodies and their binding partners. Currently, scientists are also using color molecules that emit light again when stimulated to make antibody-antigen interactions visible.
Many variants of experimental procedures have been developed and it is common to construct tests that use more than one antibody to detect the desired target.
The use of antibodies allows experiments to be designed in a variety of ways for planned analyses. To achieve the best test results, various reagents, additives and solutions should be tested for optimal combinations and concentrations, and incubation times and a number of wash cycles should be evaluated and adjusted. This is to avoid unwanted interactions that prevent the analysis from finding the desired target.
In ELISA assays, antibodies can detect immobile antigens, capture labeled antigens, capture unlabeled antigens and use a second labeled antibody to detect the captured antigen, or use a third antibody to detect, or even use two antibodies to detect.