Why is chemiluminescence used in western blotting?

Chemiluminescence is commonly used in Western blotting because it is highly sensitive, specific, and easy to perform, and is compatible with file and digital imaging. 

In addition to boosting performance efficiency, this approach is also cost-effective as the labeled secondary antibody can be reused across multiple experiments for detecting primary antibodies from the same species. Chemiluminescence in Western blotting is particularly useful for answering the question, “Is my protein present or not?”