Separation of derivatized carbohydrates by co-electroosmotic capillary electrophoresis

Abstract

SummaryThe separation of derivatized carbohydrates has been performed by co-electroosmotic capillary electrophoresis. Derivatization was performed by reductive amination of the carbohydrates with ethyl p-aminobenzoate or with p-aminobenzonitrile. Separation selectivity is optimized using buffer electrolytes containing high concentrations of borate, organic solvents, and mixtures thereof; this enabled separation of the carbohydrate derivatives then direct UV detection. Co-directional migration of the anionic analytes with the electroosmotic flow was achieved by adding a cationic polymer (hexadimethrine bromide, HDB) to the electrolyte. With this method it is possible to determine specific carbohydrates, such as arabinose, mannose, and glucose, which are difficult to separate by other CE methods. The applicability of the method is demonstrated for the analysis of plant hydrolyzates

Photochemical Charge Separation in Closely Positioned Donor–Boron Dipyrrin–Fullerene Triads

“…General screening techniques like colour reactions or thin‐layer chromatography (TLC) are only partially reliable 10. Methods like high‐performance liquid chromatography (HPLC)11, 12 or capillary electrophoresis13 deliver qualitative and quantitative information, but require the derivatisation of target molecules due to the lack of chromophores and fluorophore groups 14. In addition, time‐consuming sample preparation steps restrict throughput.…”

Evaluation of coelectroosmotic capillary zone electrophoresis for the rapid analysis of twelve aromatic sulphonate compounds

“…Because addition of organic solvents to the running buffers changes the zeta potential, viscosity, dielectric constant, and permittivity, and can improve the selectivity, resolution, and peak symmetry [33,34], several were used to optimize the separation of isomeric compounds which were not resolved by use of the coelectroosmotic aqueous systems [10,18,19,23].…”

“…The analysis time can also be reduced by reversing the EOF, a principle known as coelectroosmotic CE [8]; this has been used successfully for the analysis of anionic compounds such as inorganic anions [9][10][11][12], lowmolecular-mass organic anions [13][14][15][16], phenolic compounds [17][18][19][20], carboxylic acids [21,22], and carbohydrates [23]. Under such conditions a negative power supply causes anionic compounds to migrate in the same direction as the EOF, i.e.…”

Analysis of galactoglucomannans from spruce wood by capillary electrophoresis

“…Monosaccharides arabinose, mannose and glucose in hydrolysates have almost equal electrophoretic mobility and separation is incomplete. Separation selectivity has been improved using high borate concentration buffers (200-500 mM) or organic modifiers such as hexadimethrine bromide, acetone, acetonitrile, ethylene glycol or aliphatic alcohols (Nguyen et al 1997). High borate concentration buffers increase the Joule heating, due to the high electric current and there is big risk of participation (Ristolainen 1999).…”

“…Rydlund and Dahlman (1996) have studied xylooligosaccharides and Ristolainen (1999) has studied wood based oligosaccharides. Nguyen et al (1997) have studied separation of derivatized carbohydrates by reversed EOF and optimization of separation with different EOF modifiers.…”