SEPARATION OF CLOSELY RELATED PEPTIDES BY CAPILLARY ELECTROPHORESIS WITH A NONIONIC SURFACTANT

Separation of Angiotensin II, its derivatives and motilins, which have the same electric charge but a single different amino acid, was performed by capillary electrophoresis with a micellar pseudo-phase of nonionic surfactant, Tween 20, in the solution. The weak interaction of the micelles with the peptides enabled the separation of motilins, peptides with a long chain length. Under these conditions, the micellar phase worked more like a stationary phase in liquid chromatography.