Title: MES
CAS Registry Number: 4432-31-9
CAS Name: 4-Morpholineethanesulfonic acid
Additional Names: 2-(4-morpholino)ethyl sulfonate; 2-(N-morpholino)ethanesulfonic acid
Molecular Formula: C6H13NO4S
Molecular Weight: 195.24
Percent Composition: C 36.91%, H 6.71%, N 7.17%, O 32.78%, S 16.42%
Literature References: One of the zwitterionic N-substituted aminosulfonic acids known as Good Buffers, active in the pH range 6-8. Prepn as sodium salt: S. Malkiel, J. P. Mason, J. Org. Chem. 8, 199 (1943); as acid: N. E. Good et al., Biochemistry 5, 467 (1966). Thermodynamic parameters: C. D. McGlothlin, J. Jordan, Anal. Lett. 9, 245 (1976). Acid-base properties: A. Balikungeri, Chimia 43, 13 (1989). Interference with protein determn: P. L. Lleu, G. Rebel, Anal. Biochem. 192, 215 (1991). Use as buffer: S. C. Lee et al., J. AOAC Int. 75, 395 (1992); P. J. Henney et al., Anim. Genet. 25, 363 (1994).
Properties: Colorless crystals from alcohol/water, dec >300°. Apparent pKa at 0.1M ionic: 0°, 6.38; 20°, 6.15; 37°, 5.98. At 0.1M ionic, 25.0° ±0.1°: pKa1 1.99; pKa2 6.21. D pKa/°C -0.011. Saturation at 0°: 0.65M.
pKa: pKa at 0.1M ionic: 0°, 6.38; 20°, 6.15; 37°, 5.98; pKa1 1.99; pKa2 6.21; pKa/°C -0.011
Use: Biological buffer. |