**1. Introduction**

Phosphorus is a non-metallic element in the 5th group of the periodic table with an atomic weight of 30.97, a density of 1.82 g/cm<sup>3</sup> , and an atomic number of 15. It was discovered in 1669 by a German chemist named Hennig Brand. The melting point and boiling point of this element are 44.1 and 280°C, respectively, and its atomic radius is 1.28 angstroms. Phosphorus is never found in nature in its free state; instead, it's found combined with other elements in rocks, phosphate minerals, and all living cells. It appears as a waxy white solid with an unpleasant smell. Phosphorus is highly reactive and emits a small amount of light when it reacts with oxygen. It burns rapidly in air,

transforming into phosphorus pentoxide. This non-metal does not dissolve in water, but it is soluble in carbon disulfide [1]. Phosphorus is an essential component of biological molecules such as ATP, ADP, and DNA, and it's also found in bones and teeth. It is present in trace amounts in all the foods we eat. There are various isotopes of phosphorus; only one, 31P, is stable. The other isotopes of phosphorus are radioactive and have short half-lives ranging from a few nanoseconds to a few seconds, except for two isotopes, 32P and 33P, which have longer half-lives of 14 and 25 days, respectively. These longer half-lives make these isotopes useful for analyzing and labeling DNA.
