MES (buffer)


 * This page is about the biochemical buffering agent. For information about other meanings of MES, see MES.

MES is the common name for the compound 2-(N-morpholino)ethanesulfonic acid. It is used as a buffering agent in biology and biochemistry. Its chemical structure contains a morpholine ring. Similar pH buffering compounds include MOPS which contains a propanesulphonic moiety instead of an ethanesulphonic one. It is one of Good's buffers, with pKa value of 6.15. Melting point is approx. 300 degrees C. It is soluble up to 2 M in water. It is also useful as a non-coordinating buffer in chemistry involving metal ions, as many common buffers (e.g. phosphate and acetate) readily form coordination complexes.

It has a molecular weight of 195.2 and the formula C6H13NO4S. Synonyms include: 2-morpholinoethanesulfonic acid; 2-(4-morpholino)ethanesulfonic acid;, 2-(N-morpholino)ethanesulfonic acid; 2-(4-morpholino)ethanesulphonic acid; MES; MES hydrate; and morpholine-4-ethanesulfonic acid hydrate.

Safety
MES is reasonably safe, but skin/eye exposure should be cleaned well with water and medical aid should be sought in the case of eye exposure/swallowing/inhalation of dust. It also emits toxic fumes upon combustion, including carbon monoxide, nitrogen oxide and sulphur oxides.

MSDS : http://www.sigmaaldrich.com/cgi-bin/hsrun/Suite7/Suite/HAHTpage/Suite.HsSigmaAdvancedSearch.formAction