Oligophosphaten

Oligophosphaten, or oligophosphates, are a class of phosphate-containing compounds consisting of a short chain of phosphate units covalently linked by phosphoester or phosphoanhydride bonds. The term covers short-chain inorganic polyphosphates as well as organic derivatives in which phosphate units are attached to other moieties. Typically, oligophosphates contain two to six phosphate residues; longer chains are usually described as polyphosphates.

Common examples include diphosphate (pyrophosphate, two units), tripolyphosphate (three units), and tetraphosphate (four units). The phosphate units are linked by energy-rich bonds, and the exact connectivity varies with chemical form and salt. Inorganic oligophosphates are often discussed separately from organic derivatives such as nucleotide triphosphates, which are more specifically classified within biochemistry.

Occurrence and function: In biology, inorganic oligophosphates occur as intermediates in phosphate metabolism and as components of energy storage systems in some organisms. They can act as chelating agents and influence enzyme activity. Commercially, short-chain phosphates are used as food additives, buffering agents, and detergents’ builders due to their sequestration of metal ions and interaction with water hardness.

Synthesis and handling: Oligophosphates are prepared by condensation of phosphate units under dehydrating conditions or enzymatically by kinases and pyrophosphatases. They are typically water-soluble salts; hydrolysis to orthophosphate occurs under acidic or enzymatic conditions.

See also: phosphate, polyphosphate, pyrophosphate, nucleotide triphosphate, polyphosphate metabolism.