title: Understanding and improving direct UV detection of monosaccharides and disaccharides in free solution capillary electrophoresis.
abstract: Direct UV detection of carbohydrates in free solution capillary electrophoresis at 270 nm is made possible by a photo-oxidation reaction. Glucose, rhamnose and xylose were shown to have unique UV absorption spectra hypothesizing different UV absorbing intermediates for their respective photo-oxidation. NMR spectroscopy of the photo-oxidation end products proved they consisted of carboxylates and not malondialdehyde as previously theorized and that oxygen thus plays a key role in the photo-oxidation pathway. Adding the photo-initiator Irgacure(®) 2959 in the background electrolyte increased sensitivity by 40% at an optimum concentration of 1×10(-4) mM and 1×10(-8) mM for conventional 50 μm i.d. capillaries and for the corresponding extended light path capillaries, respectively.
authors.affiliation: University of Western Sydney, Australian Centre for Research On Separation Sciences (ACROSS), School of Science and Health, Parramatta Campus, Locked Bag 1797, Penrith NSW 2751, Australia.
authors.forename: James D
authors.initials: JD
authors.lastname: Oliver
authors.affiliation: University of New England, School of Science and Technology, Armidale NSW 2351, Australia.
authors.forename: Adam A
authors.initials: AA
authors.lastname: Rosser
authors.affiliation: University of New England, School of Science and Technology, Armidale NSW 2351, Australia.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Fellows
authors.affiliation: Aix-Marseille Université, CNRS, Institut de Chimie Radicalaire UMR 7273, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France.
authors.forename: Yohann
authors.initials: Y
authors.lastname: Guillaneuf
authors.affiliation: Aix-Marseille Université, CNRS, Institut de Chimie Radicalaire UMR 7273, Avenue Escadrille Normandie-Niemen, 13397 Marseille Cedex 20, France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Clement
authors.affiliation: University of Western Sydney, Molecular Medicine Research Group (MMRG), School of Science and Health, Parramatta Campus, Locked Bag 1797, Penrith NSW 2751, Australia.
authors.forename: Marianne
authors.initials: M
authors.lastname: Gaborieau
authors.affiliation: University of Western Sydney, Australian Centre for Research On Separation Sciences (ACROSS), School of Science and Health, Parramatta Campus, Locked Bag 1797, Penrith NSW 2751, Australia. Electronic address: p.castignolles@uws.edu.au.
authors.forename: Patrice
authors.initials: P
authors.lastname: Castignolles
mesh_terms: D004187:Disaccharides / Q000032:analysis*; D019075:Electrophoresis, Capillary; D009005:Monosaccharides / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays
chemical_list: D004187:Disaccharides; D009005:Monosaccharides
keywords: Direct UV detection; Free solution capillary electrophoresis; Nuclear magnetic resonance spectroscopy; Photo-initiator; Radical photo-oxidation; Saccharide