Countercurrent chromatographic

Kohler, N. et al.. Development of a new preparative spiral-coil low speed rotary countercurrent chromatographic (spiral-coil LSRCCC) method, J. Liq. Chromatogr. Rel. TechnoL, 27, 2547, 2004. 

Various countercurrent chromatographic techniques have been successfully employed for the separation of flavonoids. Countercurrent chromatography is a separation technique that relies on the partition of a sample between two immiscible solvents, the relative proportions of solute passing into each of the two phases determined by the partition coefficients of the components of the solute. It is an all-liquid method that is characterized by the absence of a solid support, and thus has the following advantages over other chromatographic techniques ... 

Kapadia, G.J., Oguntimein, B., and Shukla, Y.N., High-speed countercurrent chromatographic separation of biflavonoids from Garcinia kola seeds, J. Chromatogr. A, 673, 142, 1994. 

Name and acronym Centrifugal partition chromatograph (CPC) High-speed countercurrent chromatograph (HSGGG)... 

Recently, another type of CPC instrument has been manufactured by Kromaton (Angers, France), and this model is now available for commercial use. Another commercially available rotating coil instrument is the multicoil countercurrent chromatograph, introduced by Pharma-Tech Research (Baltimore, MD). The multicoU... 

Countercurrent Chromatographic Separation of Vitamins by Cross-Axis Centrifuge... 

Among various types of countercurrent chromatographic instruments developed in the past, the cross-axis coil planet centrifuge (cross-axis CPC) is one of the most useful systems for separation of numerous kinds of natural and synthetic products. 

Shinomiya, K. Inokuchi, N. Gnabre, J.N. Muto, M. Kabasawa, Y. Fales, H.M. Ito, Y. Countercurrent chromatographic analysis of ovalbumin obtained from various sources using the cross-axis coil planet centrifuge. J. Chromatogr., A 1996, 724, 179. 

Shinomiya, K. Sasaki, Y. Shibusawa, Y. Kishinami, K. Kabasawa, Y. Ito, Y. Countercurrent chromatographic separation of hippuric acid and related compounds using cross-axis coil planet centrifuge with eccentric coil assemblies. J. Fiq. Chromatogr. Relat. Technol. 2000, 23, 1575. 

Fig. 4a shows countercurrent chromatographic separation of four basic dyes, i.e., methyl green (MG), methylene blue (MB), neutral red (NR), and basic fuchsin using a two-phase solvent system composed of isoamyl alcohol-ethanol-acetic acid-distilled water (4 2 1 5, v/v). The first coil displays the separation of the mixture, and the other coils show distribution of individual dyes to demonstrate the reproducibility of the method. The separation was performed with 6 m of 0.35-mm-lD tubing (ca. 300 helical turns) at relative coil rotation of 0.25 rpm at 300 X g for 10 hr. 

Leive, L. Cullinane, M.L. Ito, Y. Bramblett, G.T. Countercurrent chromatographic separation of bacteria with known difference in surface lipopolysaccharide. J. Liq. Chromatogr. 1984, 7 (2), 403 -418. 

Marcel Dekker, Inc. All rights reserved. This material may not be used or reproduced in any form without the express written permission of Marcel Dekker, Inc. 2 Countercurrent Chromatographic Separation of Vitamins by Cross-Axis Coil Planet Centrifuge... 

Fig. 3 Countercurrent chromatographic separation of HDL-LDL and VLDL-serum protein fractions from human serum with an aqueous polymer phase system. Column 2.6mm I.D. PTFE single-layer coil (x2) with 60-mL capacity sample 4 mL of human serum solvent system 16% PEG 1000-12.5% dibasic potassium phosphate at pH 9.2 mobile phase lower phase flow rate 0.5 mL/min revolution speed 500 rpm. SF = solvent front, UP = starting point of the reversed elution mode with the upper phase.

Fig. 1 Chromatograms of hesperetin (1), kaempferol (2), and quercetin (3) by different countercurrent chromatographic methods. Solvent system chloroform-methanol-water (33 40 27). (A) DCCC (B) RLCC (C) multilayer coil CPC system and (D) cartridge CPC system. (Elsevier Science Ireland, Ltd.)...

Ito, Y. Test to evaluate countercurrent chromatographs. Liquid stationary phase retention and chromatographic resolution. CRC Crit. Rev. Anal. Chem. 1986, 17, 65-143. Berthod, A. Billardello, B. J. Chromatogr., A 2000, 902, 323-335. 

Figure 11-14. A multilayer coil-planet countercurrent chromatograph, model DP-950.

Like countercurrent distillation, the countercurrent chromatographic systems are binary separators thar is. they can make a cut between two key components. Most industrial applications have separated binary mixtures. Then the purpose of zone I in Fig. 14.3-1 is to remove the more strongly adsorbed solute B from A. Thus, in this zone solute A shonld go up and solute B should go down. In terms of the average solute velocities,... 

The ratio of these flow rates results in the follovdng dimensionless parameter that is essential for the design of countercurrent chromatographic separation (Storti et al., 1993) ... 

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