Bioluminescence:

Previously you read about the origin of chemiluminescence as a consequence of a chemical reaction. You have learnt about a few environmental applications of chemiluminescence. Measurement of light from a chemical reaction is highly meaningful since the concentration of an unknown could be inferred from the rate at that light is emitted. The rate of light output is straight associated to the amount of light emitted and accordingly, proportional to the concentration of the luminescent material present. Thus, light measurement is an associative indicator of the amount of luminescent material present in the sample of interest. The oxidation of luminol in alkaline solution is a well known instance of chemiluminescence.

The phenomenon of luminescence occurring in living systems or the compounds extracted from the living systems is called the bioluminescence.  Let us try to understand this phenomenon and its significance in analysis.

You might have seen a firefly and may also would have come across flashing fish, glinting glow worms, etc. and would have wondered about the why and how of the glow. Some natural purposes of such a glow include, attracting a mate, attracting prey, deterring predators, camouflage, and aiding in hunting, etc. Since regards the how or origin of such a glow, it is because of the result of biological processes that lead to the emission of light leading to the glow. These processes include the use of a chemical called luciferin and an enzyme called luciferase. As mentioned above, this phenomenon of emission of light by a living creature or compound extracted from living systems is called bioluminescence.