Sodium metaperiodate, Sodium periodate, 99.5+%

Sodium periodate is an inorganic salt, composed of a sodium cation and the periodate anion. It may also be regarded as the sodium salt of periodic acid. Like all periodates it can exist in two different forms: sodium metaperiodate, which has the formula NaIO4, and sodium orthoperiodate, normally this means sodium hydrogen periodate (Na2H3IO6) but the fully reacted sodium orthoperiodate salt, Na5IO6, can also be prepared. Both salts are useful oxidising agents.

Sodium periodate can be used in solution to open saccharide rings between vicinal diols leaving two aldehyde groups. This process is often used in labeling saccharides with fluorescent molecules or other tags such as biotin. Because the process requires vicinal diols, periodate oxidation is often used to selectively label the 3'-termini of RNA (ribose has vicinal diols) instead of DNA as deoxyribose does not have vicinal diols.

NaIO4 is used in organic chemistry to cleave diols to produce two aldehydes.