Abstract:
<p align="justify"> Luminescence has been known since ancient times. However, consistent theories about the mechanisms involved in this process have been proposed only during the last few decades. The luminescence phenomenon is the result of the absorption of energy by atoms or molecules followed by their de-excitation, with photon emission in the visible part of the spectrum. The source of energy that leads to the excited species in bioluminescence and chemiluminescence is a chemical reaction that may or may not involve enzymes. This paper presents a short review of the present state of knowledge about chemiluminescence and discusses some of its applications in biology and medicine </p>