Immunodiagnostics is a diagnostic method for determining immunological status and detecting diseases that relies on unique immune interactions between antigens and antibodies. Radioimmunoassay (RIA), immunocolloidal gold, enzyme-linked immunoassay (ELISA), time-resolved fluorescent immunoassay (TRFIA), and chemiluminescence immunoassay (CLIA) are examples of immunodiagnostic techniques. The main difference between them is the method of labeling the antigen or antibody to amplify and quantify the response signal.
Chemiluminescence immunoassay is progressively displacing the old enzyme-linked immunoassay technology as a critical component of precision medicine and as the primary method of medical testing.
Chemiluminescence immunoassay is the process of labeling an antigen or antibody with a luminous material or enzyme. An oxidising agent or chemiluminescent substrate is added after the antigen or antibody has specifically bound to the substance to be tested, and after oxidation or reaction with the substrate, the intensity of the chemiluminescent substance can be detected by the instrument to determine the content of the substance to be tested.
Chemiluminescence immunoassay is more sensitive than typical enzyme-linked immunoassay procedures. Tumor markers can be recognized at an early stage, which is especially useful in cancer screening and diagnosis. Traditional testing procedures for the liver cancer marker alpha-fetoprotein, for example, require more than 10 g/ml to detect the disease, but chemiluminescence immunoassay only requires 0.1 g/ml to detect the disease. Currently, chemiluminescence immunoassay analysers are used in clinical applications. In addition to tumor marker detection, they are also used with fully automatic biochemical analyser to detect diabetes, hypertension, heart disease, infectious diseases, allergic diseases, and other diseases, accounting for approximately 38 percent of laboratory medicine. With the development of precision medicine, chemiluminescence immunoassay will become a major tool in laboratory medicine.
