Enzyme-linked immunosorbent assay (ELISA) and Western blotting are two common enzyme-immunological methods used in the medical field.
ELISA is a plate-based assay that uses antibodies to detect the presence of a specific protein or antigen in a sample. The sample is added to a microplate well that has been coated with a capture antibody specific to the target antigen. After washing, a detection antibody labeled with an enzyme is added, which binds to the captured antigen. A substrate is then added, and the enzyme catalyzes a reaction that produces a detectable signal, such as a color change, indicating the presence and quantity of the target antigen in the sample.
Western blotting is a laboratory technique used to detect specific proteins in a mixture of proteins. The protein mixture is first separated by size using gel electrophoresis, then transferred to a membrane where it can be probed with antibodies specific to the target protein. A detection system such as a chemiluminescent or colorimetric substrate is used to visualize the location and quantity of the target protein on the membrane.
These enzyme-immunological methods are widely used in clinical laboratories for various diagnostic tests, including the detection of infectious diseases, allergies, and cancer markers. They offer high sensitivity, specificity, and reproducibility, making them valuable tools in medical diagnostics and research.