Typically performed in multi-well microtiter plates, ELISAs are a molecular biology assay commonly used for the detection and quantification of diverse molecules, including peptides, proteins, and antibodies.
Such assays can detect molecules of interest at pg/ml levels and are essential for both basic and disease research. Nowadays, there are many companies available from where you can easily buy bdnf elisa kit online.
Elisa Assays: Antibody-Antigen Interaction
The main molecular components of an ELISA typically include the use of enzyme-conjugated antibodies, immobilized molecules, and detection substrates.
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An important aspect that determines the success and quality of ELISA data depends on the affinity and specificity of the antibody-antigen interaction. Antigen-antibody interactions are affected by a number of factors, including pH, temperature, and ionic strength.
ELISA using the direct detection method requires an immobilized antigen bound directly to the surface of the test plate or indirectly via a capture antibody, followed by an antigen-specific primary antibody conjugated to the detection enzyme and substrate.
The more commonly used indirect detection format consists of an unconjugated primary antibody followed by a conjugated secondary antibody that is specific for detecting the primary antibody.
Indirect detection uses enhanced immunoreactivity with the target antigen, since conjugated enzyme elements are present only in secondary antibodies.
In addition to the direct and indirect detection methods, the catch or sandwich assay uses an additional antigen-capturing antibody that first binds to the surface of the microtiter plate, followed by the use of a primary and enzymatic conjugated secondary antibody, similar to the indirect method described above.