HPLC separation of all aldopentoses and aldohexoses on an anion-exchange stationary phase prepared from polystyrene-based copolymer and diamine: the effect of NaOH eluent concentration.

To investigate the separations of all aldopentoses (ribose, arabinose, xylose and lyxose) and aldohexoses (glucose, galactose, allose, altrose, mannose, gulose, idose and talose) on the D₆ stationary phase prepared by the reaction of chloromethylated styrene-divinylbenzene copolymer and N,N,N',N'-tetramethyl-1,6-diaminohexane, we examined the effect of varying the concentration of the NaOH eluent on the elution orders. Separations of these aldoses were achieved using a 20 mM NaOH eluent. The elution behaviors of the aldoses were probably due to not only the individual pK(a) values, but also the chemical structures of the cyclic aldoses.

Synthesis of monodispersed molecularly imprinted polymer particles for high-performance liquid chromatographic separation of cholesterol using templating polymerization in porous silica gel bound with cholesterol molecules on its surface.

Monodispersed molecularly imprinted polymer particles selective for cholesterol were prepared by the copolymerization of styrene and divinylbenzene in the presence of template silica gel particles (particle size: 5 μm; pore size: 10 nm) functionalized with cholesterol on the surface, followed by dissolution of the cholesterol-bonded silica gel with a NaOH aqueous solution. Transmission and scanning electron micrographs of the molecularly imprinted polymer (MIP) particles revealed good monodispersity and porous structure. The MIP particles were packed into a high performance liquid chromatographic column, and its recognition ability of cholesterol was evaluated using cholesterol, cholesterol esters and fatty acid methyl esters by comparison with the non-imprinted polymer (NIP) particles prepared from styrene and divinylbenzene without cholesterol.

Preparation of monodispersed vinylpyridine-divinylbenzene porous copolymer resins and their application to high-performance liquid chromatographic separation of aromatic amines.

For the separation of aromatic amines, two types of monodispersed porous polymer resins were prepared by the copolymerization of 2-vinylpyridine and 4-vinylpyridine with divinylbenzene in the presence of template silica gel particles (particle size 5 microm), followed by dissolution of the template silica gel in an alkaline solution. The transmission electron micrographs and the scanning electron micrograph revealed that these templated polymer resins have a spherical morphology with a good monodispersity and porous structure. Using these monodispersed polymer resins, the high-performance liquid chromatographic separation of aromatic amines in the mobile phases of pHs 2.

Complexation behavior of mono- and disaccharides by the vinylbenzeneboronic acid-divinylbenzene copolymer resins packed in a high-performance liquid chromatographic column.

Using an HPLC column packed with monodispersed vinylbenzeneboronic acid-divinylbenzene (V-D) copolymer resins, the elution behaviors of the mono- and disaccharides were studied under different pH mobile phases. The monodispersed V-D copolymer resins were prepared by the copolymerization of 4-vinylbenzeneboronic acid and divinylbenzene in the presence of template silica gel particles (particle size: 5 microm; pore size: 10 nm), followed by dissolution of the template silica gel using a NaOH solution. Similarly, styrene-divinylbenzene (S-D) copolymer resins as the control resins were also synthesized.

Quantitative determination of sugars and myo-inositol in citrus fruits grown in Japan using high-performance anion-exchange chromatography.

Fifteen commercial samples of citrus fruits grown in Japan were analyzed for their sugar contents by high-performance anion-exchange chromatography (HPAEC) and electrochemical detection (ED) coupled with a stationary phase D10 column prepared using chloromethylated styrene-divinylbenzene copolymer and N,N,N',N'-tetramethyldiaminodecane. Myo-inositol, glucose, fructose, and sucrose in all of these various citrus fruits could be successfully separated within 25 min using 0.5 M NaOH eluent at a flow-rate of 0.

High-performance liquid chromatographic separation of carbohydrates on a stationary phase prepared from polystyrene-based resin and novel amines.

New anion-exchange stationary phases On (n = 1, 2 and 3) with a dimethylamino terminal functional group, where n is the number of oxyethylene units [-(CH2CH2O)n-], were prepared by the reaction of chloromethylated porous styrene-divinylbenzene copolymer beads and amines [(CH3)2N-(CH2CH2O)nCH2CH2-N(CH3)2]. HPLC separations of monosaccharides (sorbitol, fucose, glucosamine, mannose, glucose, galactose, fructose, allose and altrose) and disaccharides (trehalose, lactose, cellobiose and maltose) were performed successfully on these stationary phases. The ether group of the stationary phases On was found to affect the separation of carbohydrates.