Sodium orthovanadate


Sodium orthovanadate is the inorganic compound with the chemical formula Na3VO4·2H2O. It is a salt of the oxyanion. It is a colorless, water-soluble solid.

Synthesis and structure

Sodium orthovanadate is produced by dissolving vanadium oxide in a solution of sodium hydroxide:
The salt features tetrahedral centers linked to octahedral Na+ sites.

Condensation equilibria

Like many oxometalates, orthovanadate is subject to a number of reactions, which have been analyzed by 51V NMR studies. At high pH, ions exist in equilibrium with. At lower pH's,
condensation ensues to give various polyoxovanadates. Ultimately, decavanadate is formed.

Biochemistry

Vanadates exhibit a variety of biological activities, in part because they serve as structural mimics of phosphates. It acts as a competitive inhibitor of ATPases, alkaline and acid phosphatases, and protein-phosphotyrosine phosphatases, and its inhibitory effects can be reversed by dilution or the addition of Ethylenediaminetetraacetic acid.
Orthovanadate is activated by boiling and adjusting pH to ~10; this depolymerizes decavanadate into the active inhibitor, monovanadate.