Sialic acids chromatography

IonPac KC-811 column separated the labile compounds N-acetylneuraminic acid and N-glycolylneuraminic acid released by mild acid hydrolysis of bovine vitronectin.245 Sialic acid is extremely labile to conditions of handling and must be released by mild acid hydrolysis.246 Derivatization with phe-nylisothiocyanate and separation by reversed phase chromatography was found useful in analysis of hexosamines from gastric mucosa.247 A review on separation of sugars and other carbohydrates which covers many important aspects is available.248... 

Hydrophilic interaction chromatography on Asahipak NH2P or Excel-pak CHA-P44 with pulsed amperometric detection has been used to fractionate malto-oligosaccharides.266 The Asahipak NH2P is a polyvinyl alcohol support with a polyamine bonded phase, and the Excelpak is a sulfonated polystyrene in the Zn+2 form. Amine adsorption of sialic acid-containing oligosaccharides was performed on a Micropak AX-5 column (Varian) using acetonitrile-water-acetic acid-triethylamine.267... 

Naturally occurring oligosaccharides have also been isolated by gel chromatography. Ohman and Hygstedt94 have reported the isolation, from colostrum, of sialic acid oligosaccharides, including di-O-sialoyl-lactose [0-A/-acetylneuraminoyl-(2 — 8)-0-(N-acetylneur-... 

Great progress in our knowledge about sialic acids was made with the aid of gas-liquid chromatography (g.l.c.), mass spectrometry (m.s.), and n.m.r. spectroscopy. Structural analysis of the many different N- andO-acylated Neu derivatives occurring in Nature will be described in Sections IV,5 and 6. 

The sialic acid eluates from ion-exchange chromatography may be evaporated by freeze-drying, or by careful rotary evaporation at a bath temperature of 35°, and stored in a deep-freezer. 

Despite treatment by ion-exchange chromatography, the sialic acid preparation may still contain such impurities as proteins, peptides, or other ionic compounds that may interfere with further analytical or preparative procedures. In these cases, chromatography of the preparation on Sephadex G-10, G-25, or Biogel P2 in water may prove helpful. 

To obtain individual sialic acids in pure, or almost pure, form, the sialic acid mixture obtained from the procedures just described are subjected to partition chromatography on cellulose powder, using, as the solvent,74107 1 2 1 (v/v/v) 1 -butanol-l-propanol-water. The (less hydrophilic) tri- and di-O-acetylated sialic acids are eluted first, followed by mono-O-acetylated sialic acids, NeuoAc, and Neu5Gc, ac-... 

Thin-layer Chromatography (Rf values) of Natural,. V,0-Acylated Sialic Acids and of the C, and C8 Analogs of Neu5Ac and Neu5Gc in System A" and in Gas-Liquid Chromatography (fiT Values, Relative to Neu5Ac = 1.00) in Systems B and C ... 

Thin-layer chromatography of 2-acylamido-2-deoxy-D-mannoses resulting from cleavage of sialic acids with acylneuraininate pyruvate-lyase is described in Ref. 107, together with the RF values of the different 0-acyl-2-acylamido-2-deoxy-D-mannose species. 

Although most of the sialidases have been purified by classical methods of enzyme isolation, affinity chromatography is now coming more and more into use, as is indicated by the foregoing examples of purification of sialidases. The adsorbent first used for chromatography of sialidases was sialic acid bound to the surface of intact erythrocytes ... 

Table 4.3.2 Diagnostic workflow of disorders with accumulation of free or oligosaccharide-bound sialic acid. MRI Magnetic resonance imaging, TLC thin-layer chromatography...

The test is performed for diagnosis of all clinical forms of SASD. This analysis is usually done after an initial TLC screening test that is positive for free sialic acid, and an increased free sialic acid value in the quantitative urine determination test. The test is like the quantitative urine test performed with the periodate-TBA assay [5, 22]. However, in this case interference is decreased by prepurification of the sample using ion-exchange chromatography [12]. Fibroblasts are cultured under standardized conditions. Cell lysates are prepared by tip sonification in distilled water and the cleared lysates are applied to small Dowex columns. NeuAc is eluted, freeze dried,... 

Ito M, Ikeda K, Suzuki Y, Tanaka K, Saito M (2002) An improved fluorometric high-performance liquid chromatography method for sialic acid determination an internal standard method and its application to sialic acid analysis of human apolipoprotein E. Anal Biochem 300 260-266... 

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