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The conformational separation of monosaccharides labeled with fluorescent 2-aminoacrydone (AMAC) was performed by electrophoresis on a plastic microchip with light-emitting diode confocal fluorescence detection. The AMAC-labeled five neutral monosaccharide mixture (D-glucose (Glc), D-mannose, D-galactose, L-fucose, and D-xylose) or two amino monosaccharide mixture (N-acetyl-D-glucosamine and N-acetyl-D-galactosamine) were well separated at pH 8.5 and 0.5% w/v methylcellulose of 200 mM borate buffer conditions using microchip electrophoresis. The separation was successfully performed considering the difference in stability of the complex between the hydroxyl residue of the monosaccharide and borate ions, and we found that 200 mM and pH 8.5 of borate buffer conditions were critical. High-speed separation for the neutral monosaccharides (50 s) and for amino monosaccharides (70 s) was attained at a 400 V/cm of electric field condition, showing all peak resolutions were greater than 0.9% and RSD of mobility were less than 1.9%. The detection limits of 0.86 microM for Glc and <1 microM for all other monosaccharides were enhanced with the addition of 0.5% w/v methylcellulose to the buffer. These attainments are fully compatible with conventional CE. The analysis of the subtle differences in the conformational stability and the value of the hydroxyl residue of the borate complex allowed the development of an efficient prospective tool for attaining high-resolution separation of monosaccharide mixtures having complicated and analogous conformations.

We developed a novel method for rapid screening of carbohydrate—protein interactions using poly(methyl methacrylate) (PMMA) channels statically coated with hydrophobically modified hydroxyethylcellulose (HM-HEC). We found that a self-assembled monolayer (SAM) of HM-HEC on a PMMA surface intact by water allows rapid and reproducible separations of glycan samples using a 20 mM phosphate without HM-HEC. The underlying mechanism for dyisamic and static coatings on the PMMA surface is discussed. Simultaneous analysis of the molecular interaction between a complex mixture of carbohydrates from (il-add glycoprotein and proteins has been successfully achieved in PMMA channels statically coated with a SAM of HM-HEC. [ABSTRACT FROM AUTHOR]