Rotation locular countercurrent chromatography

Stationary Phase Lower Phase Mobile Phase Upper Phase Flow Rale 0.5 ml/min 

When the apparatus is charged with the mobile phase, the sample is loaded into the injector loop and transferred to the first column. Within each loculus, the sample is partitioned between the mobile and stationary phases whose interface is constantly renewed by the rotation of the apparatus at 60 to 80 rpm. This rotation speed does not allow excessive agitation to occur this could result in the formation of emulsions, a problem commonly encountered in countercurrent distribution. 

Should the lighter of the two phases dissolve the larger percentage of the sample, the descending mode of operation, with the heavier phase as the mobile phase, is used. The principle is the same as in the ascending mode, but the direction of application of the mobile phase is reversed. In the descending mode, the mobile phase is applied to the top of each column and drops to the lowermost corner of each loculus (Fig. 2.12). 

Results on the early home-built models demonstrated the wide range of solvent systems applicable on RLCC. Using an aqueous methanol (5% water), petroleum ether system on an RLCC with 187 loculi, a mixture of chlorophylls (7) was resolved as well as a mixture of carotenoids (133) that had been extremely difficult to resolve by any other means - including countercurrent distribution, which had 

The application of RLCC to the fractionation and isolation of natural products has also been described. Of particular interest was the isolation of chromo- 

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The analysis of the mobile-phase fractions collected at the outlet of column is the oldest method used in CCC (droplet countercurrent chromatography and rotation locular countercurrent chromatography) to elucidate the quality of separation and to characterize solutes. With modern CCC, such as CPC, CCC type J, and crossaxis, numerous apphcations have been described for preconcentration and preparative chromatography. 

Rotation locular countercurrent chromatography is particularly suitable for the preparative separation of natural products, and the apparatus is commercially available through Tokyo Rikakikai Co., Ltd., Tokyo, Japan. 

Snyder, J.K. Nakanishi, K. Hostettmann, K. Hostettmann, M. Applications of rotation locular countercurrent chromatography in natural products isolation. J. Liq. Chromatogr. 1984, 7, 243-256. 

Kabasawa, Y. Shinomiya, K. Nakazawa, H. Tanimura, T. Fujita, M. Purification of Food Blue No. 1 by rotation locular countercurrent chromatography. Anal. Sci. 1991, 7, 273-276. 

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