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Amine-bonded chromatography

Nikolov, Z., Meagher, M., and Reilly, P., High-performance liquid chromatography of trisaccharides on amine-bonded silica columns, J. Chromatogr., 321, 393, 1985. [Pg.138]

A short column packed with an amine bonded polymer (weak anion exchange material) connected prior to the anion separation column was found to be very effective for the selective removal of humic substances prior to anion separation by ion chromatography. About 500 sample injections could be performed before breakthrough of humic substances occurred as indicated by ultraviolet measurements made on the eluate at 225nm. [Pg.52]

In recent years the solid-phase hydrosilylation reaction was successfully employed for synthesis of hydrolytically stable surface chemical compounds with Si-C bonds. Of special interest is application of this method for attachment of functional olefins, in particular of acrolein and some chiral ligands. Such matrices can be used for subsequent immobilization of a wide range of amine-containing organic reagents and in chiral chromatography. [Pg.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... [Pg.254]

The TLC process is an off-line process. A number of samples are chromatographed simultaneously, side-by-side. HPTLC is fast (5 min), allows simultaneous separation and can be carried out with the same carrier materials as HPLC. Silica gel and chemically bonded silica gel sorbents are used predominantly in HPTLC other stationary phases are cellulose-based [393]. Separation mechanisms are either NPC (normal-phase chromatography), RPC (reversed-phase chromatography) or IEC (ion-exchange chromatography). RPC on hydrophobic layers is not as widely used in TLC as it is in column chromatography. The resolution capabilities of TLC using silica gel absorbent as compared to C S reversed-phase absorbent have been compared for 18 commercially available plasticisers, and 52 amine and 36 phenolic AOs [394]. [Pg.221]

The most popular and versatile bonded phase is octadecylsilane (ODS), n-C18H37, a grouping that is non-polar and used for reverse phase separations. Octylsilane, with its shorter chain length, permits faster diffusion of solutes and this results in improved peak symmetry. Other groups are attached to provide polar phases and hence perform normal phase separations. These include cyano, ether, amine and diol groups, which offer a wide range of polarities. When bonded stationary phases are used, the clear distinction between adsorption and partition chromatography is lost and the principles of separation are far more complex. [Pg.115]

S.O. Jansson, Effect of counter-ions in ion-pair liquid chromatography of hydrophobic amines on non-polar bonded phases , J. Liq. Chromatogr., 1982, 5, 677. [Pg.95]

An early demonstration of the power of hetaeric chromatography in bonded reversed>phase systems was made by Wittmer et al. (216) who showed the effect of tertiary and quaternary amines in the mobile phase ixi Ihr sepai iiiion of lartru/iiic, a Milfonic acid dye, aiul inlcrnicdiiiles in its synthesis. Figure 45 reproduces a chromatogram obtained by them with this technique. [Pg.118]

As shown by mass spectrometry and NMR spectroscopy, these amine derivatives of Cgfl, after work up, are dehydrogenated adducts [81]. After nucleophilic addition, the H atoms brought in by the diamines were oxidatively eliminated. The final adduct formation of the secondary diamines proceeds exclusively at [6,6] bonds. Besides the monoadduct, most of the regioisomeric bisadducts of piperazine or N,N -dimefhylethylenediamine and Cjq could be separated by column chromatography. The structure of the monoadduct and some of these bis-adducts were proven by X-ray crystal-structure analysis [90]. [Pg.89]


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