Results 151 to 160 of about 1,452 (205)

High-Speed Countercurrent Chromatography

Critical Reviews in Analytical Chemistry, 1986
I. INTRODUCTION During the past 20 years countercurrent chromatography (CCC) has been steadily improved in both partition efficiency and separation times.1-15 The original helix CCC and the successively developed nonhelix preparative-scale CCC schemes, such as droplet CCC16,17 and locular CCC,17 required relatively long separating times; sizeable ...
Yoichiro Ito, Walter D. Conway
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Chiral Separation by High-Speed Countercurrent Chromatography

Analytical Chemistry, 1995
Various parameters involved in the chiral separation of (+/-)-DNB-amino acids were investigated using N-dodecanoyl-L-proline-3,5-dimethylanilide as a chiral selector (CS) and two-phase solvent systems composed of hexane/ethyl acetate/methanol/10 mM hydrochloric acid at various volume ratios.
Y, Ma, Y, Ito
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Development of High-Speed Countercurrent Chromatography

2021
The preparative capability of the multilayer coil has been demonstrated in the separation of 1 g of the DNP amino acid mixture under the optimal operational conditions determined by the preliminary studies on short coils as described above. These centrifuge schemes are equipped with a novel flow-through mechanism which entirely eliminates the need for ...
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Analytical High Speed Countercurrent Chromatography

Journal of Liquid Chromatography, 1988
Abstract The resolution of countercurrent distribution has long been demonstrated. However, the long elution time limits its analytical applications. The development of a high speed planet centrifuge has markedly improved the efficiency of the system; thus the countercurrent chromatography can be completed within several hours instead of days.
Y.-W. Lee, Y. Ito, Q.-C. Fang, C. E. Cook   +3 more
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High-speed countercurrent chromatography

Nature, 1987
Support-free high-speed countercurrent liquid chromatography provides a rich domain of applications, some beyond reach of conventional liquid chromatography.
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PURIFICATION OF YTTRIUM BY HIGH-SPEED COUNTERCURRENT CHROMATOGRAPHY

Journal of Liquid Chromatography & Related Technologies, 1999
Separation of rare earth elements has been studied by high– speed countercurrent chromatography (CCC) employing 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester in toluene as a stationary phase. The CCC method was applied to purification of rare earth elements in a wide range of concentrations. High-purity yttrium was chromatographically isolated by
Shigeto Nakamura, Hiroyuki Hashimoto, Kenichi Akiba   +2 more
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Purification of Curcumin, Demethoxycurcumin, and Bisdemethoxycurcumin by High-Speed Countercurrent Chromatography

Journal of Agricultural and Food Chemistry, 2008
Curcuminoids are substances of great interest because of their important pharmacological activities, particularly anti-inflammatory, anticarcinogenic, and anti-Alzheimer's activities. In this study, we report the first procedure and effect of processing for the high, efficient, and useful purification of curcumin, demethoxycurcumin, and ...
Koichi, Inoue, Chihiro, Nomura, Sumio, Ito, Akito, Nagatsu, Tomoaki, Hino, Hisao, Oka   +5 more
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Concentration of Heavy Metals by High-Speed Countercurrent Chromatography

Journal of Liquid Chromatography & Related Technologies, 1998
Application of high-speed countercurrent chromatography (HSCCC) to the concentration of metal ions has been studied. The stationary phase, containing di(2-ethylhexyl) phosphoric acid (DEHPA) in n-heptane, was continuously fed into the column. The ppb level of metal ions in a 500 mL of the mobile phase was continuously concentrated into small volumes of
E. Kitazume, N. Sato, Y. Ito
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Separation of heavy metals by high-speed countercurrent chromatography

Analytical Chemistry, 1993
Separation of heavy metal elements such as Co, Cu, Fe(II),Fe(III), Mg, and Ni was performed with a high-speed CCC coil planet centrifuge equipped with a multilayer coil. The two-phase solvent systems used for the separation were composed of n-heptane containing bis(2-ethylhexyl) phosphoric acid (stationary phase) and diluted citric acid (mobile phase),
Eiichi. Kitazume, Nobuyoshi. Sato, Yoshihiro. Saito, Yoichiro. Ito   +3 more
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Preparative Separation of Polyphenols from Tea by High-Speed Countercurrent Chromatography

Journal of Agricultural and Food Chemistry, 2000
High-speed countercurrent chromatography (HSCCC) was applied to the separation of polyphenols from tea leaves (Camellia sinensis L.). The capability of HSCCC to isolate pure tea polyphenols from complex mixtures on a preparative scale was demonstrated for catechins, flavonol glycosides, proanthocyanidins, and strictinin from green and black tea.
A, Degenhardt, U H, Engelhardt, C, Lakenbrink, P, Winterhalter   +3 more
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