2-Morpholinoethanesulfonic Acid (MES)

2-Morpholinoethanesulfonic Acid (MES) structural formula

CAS Number 4432-31-9
Molecular Formula C6H13NO4S
Molecular Weight 195.230 g/mol
LogP -2.12
  • 4-Morpholineethanesulfonic acid
  • 2-(Morpholin-4-yl)ethane-1-sulfonic acid
  • 4432-31-9
  • BRN 0141319
  • EINECS 224-632-3
  • Ethanesulfonic acid, 2-morpholino-
  • Morpholineethanesulfonic acid
  • Morpholinoethanesulfonic acid
  • Morpholino-N-ethylsulfonate
  • NSC 157116
  • 2-(4-Morpholinyl)ethanesulfonic acid
  • UNII-2GNK67Q0C4
  • 2-(N-Morpholino)aethansulfonsaeure
  • 2-(N-Morpholino)ethansulfonsaeure
  • 2-(N-morpholino)ethanesulfonic acid
  • 2-(morpholin-4-yl)ethanesulfonic acid
  • 2-morpholin-4-ylethanesulfonic acid
  • 2-morpholinoethanesulfonic acid
  • 2-morpholinoethanesulphonic acid
  • 4-morpholinethanesulfonic acid
  • MES


HPLC Separation of Morpholino Sulfates

MOPS and MES are buffers used in biology and biochemistry. They consist of a morpholine ring and propanesulfonic acid. Both molecules are zwitter-ionic and very polar. No retention can be achieved on reversed-phase columns. MOPS and MES are analyzed in HILIC mode on a Primesep N HPLC column. Other biological buffers can be analyzed with this general method. Biological buffers are not UV active and can be monitored by ELSD, CAD or LC/MS.

Application Analytes:

2-Morpholinoethanesulfonic Acid (MES)
4-Morpholinepropanesulfonic Acid (MOPS)

Effect of Buffer on HPLC Separation of Buffers

HEPES, CAPS, MES and MOPS are zwitterionic organic chemical buffering agents. These are very polar compounds which are not retained by traditional reverse phase chromatography. These compounds are zwitterions in nature and can be separated by mixed-mode hydrophilic interaction chromatography on Obelisc N column. Retention is achieved by combination of HILIC and ion-exchange mechanisms. These buffering agents do not have UV active groups, but can be analyzed with ESLD, LC/MS, and CAD detection.

Application Analytes:

2-Morpholinoethanesulfonic Acid (MES)
4-Morpholinepropanesulfonic Acid (MOPS)
CAPS (3-(Cyclohexylamino)propanesulfonic acid)
HEPES (4-(2-hydroxyethyl)-1-piperazineethanesulfonic Acid)