Development and validation of a capillary electrophoresis method for the determination of sulfate in effervescent tablets

Capillary zone electrophoresis of lipoarabinomannan by multi-layered concentration

The present paper describes a capillary zone electrophoresis method which relies on a multi-layered water-alkali solvent stacking with on-line ionization to enhance detection of mannose, arabinose, and their oligosaccharides, which are used as the migration profile standards but are also the distinctive structural components of lipoarabinomannan. Lipoarabinomannan is detected in patients having tuberculosis. The CE method with ionization of the whole saccharides without degradation in alkaline solution inside the capillary is based structural deprotonation of the molecules under ultrahigh pH conditions. The validation of the CE parameters revealed that the 15-fold electrolyte - water -injection plug allowed detection of one third lower concentrations than detected without on-line concentration. For the first time, the better detectability was seen especially for highly polymerized, but otherwise poorly ionized, arabino-octaose. The applicability of the method for detecting whole large biological saccharide complexes was confirmed by the glycolipid lipoarabinomannan. For the first time also, the migration of the indestructible lipoarabinomannan was detected together with oligosaccharides used representing the capping units, namely mannose, mannobiose and mannotriose. The myo-inositol-phosphate-lipid unit was seen to migrate separately from the arabinomannan, since it was hydrolyzed from one lipoarabinomannan product under alkaline conditions in CE. This article is protected by copyright. All rights reserved.