Coil Countercurrent Chromatography

Coil countercurrent chromatography (coil-CCC) is based on two systems, both developed by Ito (170, 176, 177, 183, 185). The simpler of the two is the hydrostatic equilibrium system, HSES (Fig. 2.1a), which employs a stationary coil. While 

To date, the number of reports on the application of coil-CCC to the isolation of natural products is still limited. The variety of structural types exemplified in these reports, however, indicates the versatility of the technique. Initial examples dealt mainly with DNP-amino acids (53, 54, 162, 171, 173, 178, 181, 184, 236, 237, 329). Recently, successful resolutions of many other compounds have been reported Mandava and Ito demonstrated the analytical utility of coil-CCC in the separation of various plant hormones, including the indole auxins (Fig. 2.5), gib-berellins, and cytokinins (248, 249, 250). Other results include the chromatography of dipeptides, gramicidins, purines, pyrimidines, and other molecules (66, 184, 208, 209, 239). All these separations employed the centrifugal planetary coil in the synchronous mode with sample loads of up to 1 g (176, 255). 

A non-synchronous centrifugal planetary coil system has also been reported (182, 376). This countercurrent apparatus is similar to that used for the synchronous mode of coil-CCC, but has the added sophistication of an adjustable revolution rate of the coil hence, the rate of revolution of the coil need not be synchronous to the rate of planetary rotation of the apparatus. (This method is occasionally referred to as planetary coil-CCC (PCCC).) Such flexibility is advantageous when the rate of coil revolution must be reduced to prevent emulsification of the two phases, which would result in transport of the stationary phase from the coil. This situation arises when there is low interfacial tension, as frequently occurs when separating macromolecules or partitioning intact cells with aqueous polymer phase systems. For instance, the nonsynchronous mode of centrifugal PCCC was successfully applied to the resolution of mammalian erythrocytes (183). This ability of aqueous solutions of two different polymers to form a two-phase liquid system allows for liquid-liquid partitioning between two aqueous phases (391). 

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Vidal, S. et al., Fractionation of grape anthocyanin classes using multilayer coil countercurrent chromatography with step gradient elution. J. Agric. Food Chem. 52, 713, 2004. 

J. L. Sandlin and Y. Ito, Gram quantity separation of DNP (dinitrophenyl) amino acids with multi-layer coil countercurrent chromatography (CCC), /. Liquid Chromatogr. 7(2) 323-340 (1984). 

Other methods have also been successfully employed in the isolation procedure of stilbenoids, including MPLC [209,299,326], preparative TLC [208,277,299], centrifugal partition chromatography (CPC) [359,360] and the support-free technique of multilayer coil countercurrent chromatography (MLCCC) [32]. A method based on capillary electrophoresis with electrochemical detection (CE-ED) was employed for the determination of oligomeric stilbenes found in the roots of Caragana species [361]. 

Matsuda, K. Matsuda, S. Saito, M. Ito, Y. Separation of phospholipids and glycoUpids using analytical toroidal-coil countercurrent chromatography. I. Separation of human hrain lipids. J. Liq. Chromatogr. Relat. Technol. 2002, 25, 1255-1269. 

The taste and mouthfeel properties of three different types of tannin-like polyphenolic compounds, representative of some of the tannin-like polyphenolic compounds found in red wines, were determined using descriptive sensory analysis [50]. Ethyl-bridged fiavan-3-ols were produced by reaction of (+)-catechin with acetaldehyde under acidic conditions. Red-colored tannin-like polyphenolic compounds from wine and from wine pomace were isolated by multilayer coil countercurrent chromatography (MLCCC). Mouthfeel attributes and bitterness of the fractions dissolved in a model wine (MW) medium were rated while the fractions were held in the mouth and after expectoration. The sensory properties... 

Flanagan S D, Johansson G, Yost B, Ito Y, Sutherland IA 1984 Toroidal coil countercurrent chromatography in the affinity partitioning of nicotinic cholinergic receptor enriched membranes. J Liq Chromatogr 7 385-402... 

Sutherland I A, Heywood-Waddington D, Peters T J 1984 Toroidal coil countercurrent chromatography a fast simple alternative to countercurrent distribution using aqueous two phase partition. J Liq Chromatogr 7 363-384... 

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