Countercurrent partition chromatograph

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

Martin and Porter (19) described a partition chromatographic procedure and first demonstrated the presence of at least one minor active component in the crystalline enzyme preparation. King and Craig (20) found a solvent system permitting effective countercurrent distribution of ribonuclease, ethanol water ammonium sulfate in the ratios 25.9 -57.6 16.5. The principal component of the Kunitz preparation behaved as an almost ideal solute with a partition ratio of 0.8. Albertsson has provided a liquid polymer countercurrent system based on dextrari and methyl cellulose (21). 

Countercurrent chromatography (CCC), as a support-free liquid-liquid partition chromatographic separation tech-... 

Compared with chromatographic methods, this countercurrent distribution method is probably less efficient, the apparatus required is very much more complicated, and the labor involved is considerably greater nevertheless, it possesses several definite advantages over chromatographic methods. The chief of these is the absence of any solid phase, which may act as an adsorbent for the solutes. In partition chromatographic methods this adsorption may often lead to distortion of the bands and render fractionation very inefficient. The behavior of a solute on a countercurrent distribution depends only on its partition coefficient, which in most cases is constant, so that it is possible to calculate the exact theoretical distribution curve and this may be used as a very sensitive test for purity. 

High-speed countercurrent chromatography (HSCCC) is a relatively new technique. It is a liquid-liquid partitioning chromatographic method in which the stationary phase is immobilized by a centrifugal force. HSCCC is the most advanced form of CCC in terms of partition efficiency and separation time. As solvent system, a mixture in different ratio is usually used, depending on the flavonoids nature ethyl acetate/... 

The great leap forward for chromatography was the seminal work of Martin and Synge (7) who in 1941 replaced countercurrent liquid-liquid extraction by partition chromatography for the analysis of amino acids from wool. Martin also realized that the mobile phase could be a gas rather than a liquid, and with James first developed (8) gas chromatography (GC) in 1951, following the gas-phase adsorption-chromatographic separations of Phillips (9). 

Alternatively, solvent partition or countercurrent techniques may be applied. In order to obtain an isoflavonoid-rich fraction from Erythrina species (Leguminosae) for further purification work, an organic solvent extract was dissolved in 90% methanol and first partitioned with hexane. The residual methanol part was adjusted with water to 30% and partitioned with t-butyl methyl ether-hexane (9 1). This latter mixture was then chromatographed to obtain pure compounds. ... 

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 ... 

Countercurrent Chromatography Countercurrent chromatography (CCC) or centrifugal partition chromatography (CPC) has gained much attention in recent years for isolation of polyunsaturated fatty acids. This new liquid chromatographic technique uses liquid-liquid partition, countercurrent distribution of solute mixmre between two liquid phases, in the absence of a solid support, to perform separation of complex mixture of chemical substances (44, 45). 

High speed countercurrent chromatography (HSCCC) produces highly efficient chromatographic separations of solutes without the use of solid supports Thus the method eliminates all complications caused by the solid support, such as adsorptive loss and deactivation of samples, tailing of solute peaks, contamination, etc. As with other CCC schemes, HSCCC utilizes two immiscible solvent phases, one as a stationary phase and the other as a mobile phase, and the separation is highly dependent on the partition coefficient values of the solutes, i.e., the ratio of the solute concentration between the mobile and stationary phases. Therefore the successful separation necessitates a careful search for the suitable two-phase solvent system that provides an ideal range of the partition coefficient values for the applied sample. 

Sato, Y. Shinomiya, K. Kabasawa, Y. Aqueous two-phase partitioning method by using rotation locular countercurrent chromatograph-an apphcation to enantiomeric separation. J. Chem. Soc. Japan 1994, 1067-1071. 

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