Electrophoresis, Vol.25, No.9, 1201-1210, 2004
Single-isomer sulfated alpha-cyclodextrins for capillary electrophoresis. Part 2. Hexakis(6-O-sulfo)-alpha-cyclodextrin: Synthesis, analytical characterization, and initial screening tests
The second member of the family of single-isomer sulfated alpha-cyclodextrins, the sodium salt of hexakis(6-O-sulfo)-alpha-cyclodextrin (HxS), has been synthesized, analytically characterized, and used as the resolving agent for the capillary electrophoretic separation of the enantiomers of nonionic, weak-acid and weak-base analytes present in our initial screening kit. HxS interacted less strongly with many of the analytes tested than the larger-ring analogs, heptakis(6-O-sulfo)-beta-cyclodextrin (HS) and octakis(6-O-sulfo)-gamma-cyclodextrin (OS). For some of the analytes, the separation selectivities obtained with HxS were complementary to those observed with hexakis(2,3-di-O-acetyl-6-O-sulfo)-alpha-cyclodextrin (HxDAS), HS, and OS. For all analytes, the effective mobilities and separation selectivities as a function of the background electrolyte concentration of HxS followed the trends that were found for HxDAS, HS, and OS.
Keywords:enantiomer separation;hexakis(6-O-sulfo)-alpha-cyclodextrin;single-isomer sulfated alpha-cyclodextrin;sulfated alpha-cyclodextrin