Saccharides separation

Fig. 3-25. Gradient elution of different sugar alcohols and saccharides. - Separator column Ion Pac AS6A eluent (A) water, (B) 0.05 mol/L NaOH + 0.0015 mol/L acetic acid gradient 7% B isocratically for 15 min, then to 100% B in 10 min flow rate 0.8 mL/min detection pulsed ampero-metry on a Au working electrode (post-column addition of NaOH) injection volume 50 pL solute concentrations 15 ppm inositol (1), 40 ppm sorbitol (2), 25 ppm fucose (3), deoxyribose (4), 20 ppm deoxyglucose (5), 25 ppm arabinose (6), rhamnose (7), galactose (8), glucose (9), xylose (10), mannose (11), fructose (12), melibiose (13), isomaltose (14), gentiobiose (15), cellobiose (16), 50 ppm turanose (17), and maltose (18).

Fig. 3-105. Separation of various sugar alcohols and saccharides. - Separator column CarboPac PA-1 eluent 0.15 mol/L NaOH flow rate 1 mL/min detection pulsed amperometry at a Au working electrode injection volume 50 pL solute concentrations 10 ppm xylitol, 5 ppm sorbitol, 20 ppm each of rhamnose, arabinose, glucose, fructose, and lactose, 100 ppm sucrose and raffmose, 50 ppm maltose.

Chemically modified alkylamine columns are the most widely used stationary phase for saccharide separations and are generally eluted with mobile phases consisting of acetonitrile-water mixtures. This mixture has been found to be far superior to others such as methanol-water (Rabel et al., 1976) and ethyl acetate-ethanol-water (Binder, 1980). It has been observed that as the water content of the mobile phase is increased the retention of saccharides is decreased. The columns are usually stable for periods of up to 3 months but... 

C.H. LochmHller and W.B. Hill, Jr. Saccharide separations in reversed-phase high-performance liquid chromatography using JL-alkyl amine nobile-phase additives. J. Chrom. 264 ... 

Fig. 3-175. Gradient elution of phos-pho lated mono- and di-saccharides. -Separator column CarboPac PAl eluant (A) 0.1 mol/L NaOH, (B) 0.1 mol/L NaOH -i-1 mol/L NaOAc gradient linear, 10% B to 20% B in 20 min, then to 50% B in 10 min flow rate 1 mL/min detection pulsed amperomet7 on a Au working electrode injection volume 50 pL solute concentrations 22.6 mg/L a-D-galactosamine-l-P (1), 9 mg/L a-D-glucosamine-l-P (2), 35 mg/L each of...

Fig. 9-160. HPAEC-PAD chromatogram of a strawberry yoghurt containing fructooligo-saccharides. - Separator column CarboPac PAl eluant NaOH/ NaOAc gradient flow rate ...

The separation was carried out on a TSKgel Amide-80 column 4.6 mm i.d. and 25 cm long with a mobile phase consisting of a 80% acetonitrile 20% water mixture. The flow rate was 1 ml/min and the column was operated at an elevated temperature of 80°C. The saccharides shown were 1/ rhamnose, 2/ fucose, 3/ xylose, 4/ fructose, 5/ mannose, 6/ glucose, 7/ sucrose and 8/ maltose. The analysis was completed in less than 20 minutes. These types of separations including other biomonomers, dimers and polymers are frequently carried out employing refractive index detection. 

Ion chromatography can be used in unique ways and by appropriate modification can often be applied to the separation of mixtures where the components themselves do not ionize or do not normally produce interactive ions in aqueous solution. A good example of this type of separation is afforded by the analysis of saccharide mixtures using ion exchange interactions. An illustration of such a separation is given in figure 15. 

Cyclic acetals formed by the reaction of saccharides or saccharide derivatives with aldehydes or ketones are named in accordance with 2-Carb-24.1, bivalent substituent names (formed by general organic nomenclature principles) being used as prefixes. In indicating more than one cyclic acetal grouping of the same kind, the appropriate pairs of locants are separated typographically when the exact placement of the acetal groups is known. 

A structural study on lipid A and the O-specific polysaccharide of the lipopoly-saccharide from a clinical isolate of Bacteroides vulgatus from a patient with Crohn s disease was conducted by Hashimoto and coworkers [39]. They separated two potent virulence factors, capsular polysaccharide (CPS) and lipopolysaccharide (LPS), from a clinical isolate of B. vulgatus and characterized the structure of CPS. Next, they elucidated the strucmres of O-antigen polysaccharide (OPS) and lipid A in the LPS. LPS was subjected to weak acid hydrolysis to produce the lipid A fraction and polysaccharide fraction. Lipid A was isolated by PLC, and its structure was determined by MS and NMR. 

Jackson, P., The use of polyacrylamide-gel electrophoresis for the high-reso-lution separation of reducing saccharides labeled with the fluorophore 8-ami-nonaphthalene-l,3,6-trisulfonic acid. Detection of picomolar quantities by an imaging system based on a cooled charge-coupled device, Biochem. ]., 270, 705, 1990. 

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