Effects of amine modifiers on the separation of tetramethylrhodamine-labeled mono- and oligosaccharides by capillary zone electrophoresis

In this work, nine tetramethylrhodamine (TMR) labeled isomeric oligosaccharide derivatives of βGal(1→4) βGlcNAc-O-TMR were separated by capillary zone electrophoresis coupled with laser-induced fluorescence detection. Charged species were created in situ by complexation with borate and phenylborate. Micellar separation was achieved by addition of 10 mM sodium dodecylsulfate to the running buffer. We have investigated the effects of adding a homologous series of monoamine modifiers on the separation efficiency of these oligosaccharides. The separation was significantly improved in the presence of the organic modifiers methyl- and ethylamines, but worsened in the presence of propyl- and butylamines. Possible mechanisms of the amine additives are discussed.