Indirect ELISA
- It detects whether an antibody is present in the sample or not.
- The antigen binds to the wells of the microtiter plate.
- A sample containing antibodies is added to the antigen-coated well and bound to the antigen.
- The free primary antibody is washed away and the antigen-antibody complex is detected by adding the secondary antibody that is bound to the enzyme capable of binding to the primary antibody.
- All the free secondary antibodies will be washed away and a specific substrate is added to give a colored product.
- Absorbance measurement of the colored product is done by spectrophotometer.
What is ELISA? – Introduction, Procedure, Types, Applications
A basic array technique called enzyme-linked immunosorbent assay that basically used to identify and measure the antibodies, proteins, peptides, and hormones in the blood. Its test result can provide us the information about the disease that may help in planning treatment. It compares with other antibody assays to provide quantitative results and separation of non-specific and specific interactions caused by continuous binding to solid surfaces, usually polystyrene multiwell plates.
Antigen (Ag)
A toxic molecule or any foreign matter that causes an immune response in the body is called an antigen. In immunology, an antigen term originally referred to substances that generate antibodies. Antigens can be proteins, peptides, lipids, or nucleic acids.
Antibody (Ab)
An antibody is a blood protein that is produced in our body by the immune system in response to and to counteract a specific antigen. Antibodies are also called immunoglobulins.