Use of countercurrent chromatography

Lipoprotein Separation by Combined Use of Countercurrent Chromatography and Liquid Chromatography... 

Putterman G J, Spear M B, Perini F 1984 Synergistic use of countercurrent chromatography and high performance liquid chromatography for the purification of synthetic peptides. J Liq Chromatogr 7 341-350... 

J.-M. Menet and M. C. Rolet-Menet, Characterization of the solvent systems used in countercurrent chromatography, in Countercurrent Chromatography, (J. M. Menet and D. Thiebaut, eds.), Marcel Dekker, Inc., New York, 1999. 

The IR-spectra of 41 tobacco alkaloids and related compounds have been tabulated (S5). Nornicotine, nicotine, myosmine, nicotyrine, anabasine, anatabine, and dihydronicotyrine were separated from an extract of tobacco alkaloids by countercurrent partition (86). Thin-layer chromatography has been used to separate nicotine, nornicotine, anabasine, and nicotyrine (57). The use of gas chromatography to separate tobacco alkaloids has been studied. The retention times of 11 tobacco alkaloids on polyethylene glycol columns has been reported (88) and the effect of the column packing on the retention times of pyridine bases has been described (89). Mixtures containing pyrrolidine, piperidine, pyridine, and various alkylated pyridines have been separated using programed temperature control (90). 

Fedotov, P.S. Maryutina, T.A. Grebneva, O.N. Kuz min, N.M. Spivakov, B.Ya. Use of countercurrent partition chromatography for the preconcentration and separation of inorganic compounds group extraction of Zr, Hf, Nb, and Ta for their subsequent determination by inductively coupled plasma atomic emission spectrometry. J. Anal. Chem. 1997,52,1034. 

As in all forms of countercurrent chromatography, the mobile and stationary phases should be equilibrated prior to use to prevent variation of the composition of two phases due to equilibration in the instrument. In some instances, however, this in situ equilibration can be utilized as a gradient-type technique to separate otherwise unresolvable compounds. 

Controversies about nomenclature have accompanied CCC since the early development of the first apparatus. The very name of the technique has been a matter of controversy as in most cases there is absolutely no countercurrent circulation only one of the liquids flows, while the other is stationary. Moreover, a significant number of reports uses the countercurrent chromatography terms when referring to simulated moving bed (SMB), a liquid-solid continuous modality of liquid chromatography [22,23]. 

Fractionation of TB could be the first example of the use of countercurrent centrifugal chromatography chromatography) with marine natural products (Bruening et al., 1986). 

The acceptable separation of Am(III) and Cm(III) by countercurrent chromatography (CCC) was achieved using both isocratic elution, and a new approach to the creation of the reagent concentration gradient in the stationary phase [1]. This way allows reduce the experiment length. 

Several chromatographic modes will be reviewed in this respect, and most will make use of a chiral support in order to bring about a separation, differing only in the technology employed. Only countercurrent chromatography is based on a liquid-liquid separation. 

Degenhardt, A. et al.. Isolation of black tea pigments using high-speed countercurrent chromatography and studies on properties of black tea polymers, J. Agric. Food Chem., 48, 5200, 2000. 

Both GC and LC may be operated in one of several modes. The principal modes currently used for large-scale separations are elution, selective adsorption or desorption, and simulated countercurrent chromatography. In addition, reaction and separation can be combined in a single column with unique advantages. Elution is the most used and best developed form of the technique and is described first. 

The three main modes of chromatographic operation are elution chromatography, selective adsorption/desorption, and simulated countercurrent chromatography. Of these, elution chromatography, used as a cyclic batch process, was the first to be developed for large-scale separations. 

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