Chemiluminesence
Emission of light caused by chemical reaction is referred to as chemiluminescence. Compared to Fluorescence and Phosphoresence, excitation by a light source is not required.
Some reactions that cause increased chemiluminescence occur in solutions; they are used for chemical analysis. To generate chemiluminescence, commercialized GC detectors use, for example, ozone, molecular fluorine, and sodium vapor. In HPLC applications, the reactions of luminol, lucigenin, and oxalate esters are often used.
Chemiluminescence detection is more sensitive than fluorescence detection as there is no disturbance by the diffused light of an excitation light source. It is often possible to use a fluorescence detector for chemiluminescence detection by turning off the lamp.