CCC Instrument Types and Manufacturers
Countercurrent chromatography, being based on the partitioning of individual solutes in immiscible solvent phases, has its origins in the work of Archer John Porter Martin and Richard Laurence Millington Synge (Martin and Synge, 1941; Synge, 1946) carried out in Britain during WWII. For their pioneering work, Martin and Synge shared the 1952 Nobel Prize in Chemistry.
Soon after their work appeared, Lyman Creighton Craig and Otto Post developed an apparatus that essentially consisted of a series of separatory funnels (“tubes”) (Craig and Post, 1949). The sample was “automatically” transferred through the apparatus and over 1000 mixing and separation steps could be achieved in a day. Individual components were separated based on their partitioning behavior. Craig and Post continuously improved their apparatus and were commercially quite successful, as judged from the number of publications that appeared citing the use of the “Craig-Post apparatus” (over 1000 publications on “countercurrent distribution” during the period 1950-1970). It should be pointed out that particular solvent systems developed decades ago for separations on the “Craig-Post apparatus” are still valid today and can be successfully used with modern machines with little or no modication.
In the early 1970s, Ito and his colleagues at NIH introduced “Droplet countercurrent chromatography” (DCCC) (Tanimura, Pisano, Ito et al., 1970). In DCCC, as with the Craig-Post apparatus, the stationary phase was held in place only with unit gravity. In contrast to modern instruments that employ centrifugal force fields much greater g, DCCC is characterized by extremely low flow rates (solute retention measured in days) and is limited only to those biphasic solvents systems that form stable droplets. Once again, however, it is noteworthy that any solvent system developed for a particular DCCC separation can be transferred to any modern instrument.
Modern CCC instruments are characterized as either hydrodynamic (HSCCC) or hydrostatic (CPC) machines. For historical reasons outlined in Berthod’s book, hydrodynamic machines are referred to as “high-speed countercurrent chromatography” (HSCCC) whereas hydrostatic machines are designated “centrifugal partition chromatography” (CPC). As with HPLC, all CCC instruments require a pump, detector and fraction collector. The only difference is the "column". For an excellent comparison of these complementary techniques, see Berthod's book (Berthos 2002).
instruments contain (1) helically coiled tubing that rotates
on its own axis and (2) a gear assembly arranged such that the helical
coils revolve around a central axis to achieve planetary motion. In contrast
to CPC, there are no rotating seals. As with CPC (and DCCC, but also
HPLC), HSCCC instruments have two orifices. Typically, instruments
are configured such that one orifice serves as an inlet where the sample
and solvents are introduced and the other as an outlet from which fractions
elute. The inlet and outlet tubing may be switched back and forth,
depending on whether the heavier (lower phase) or the lighter (upper)
phase of the binary system is chosen as the mobile phase.
In CPC machines there is a single axis of rotation. Many individual locules (cartridges, tubes, channels, etc.) are arranged on a rotor and connected in series. When the rotor is set in motion, a constant (hydrostatic) force field is observed at each radius. This configuration necessitates the use of a rotary seal. Users of early CPC instruments were often frustrated by problems with a leaking rotary seal. Significant efforts have been applied to this problem and the seals on modern CPC instruments are quite stable.
Link to an alphabetic list of manufacturers.
Berthod, A, Ed. Countercurrent Chromatography: The support-free liquid stationary phase (Wilson & Wilson's Comprehensive Analytical Chemistry Vol. XXXVIII); Elsevier Science Ltd.: Boston, 2002.
Conway, Walter D., Ed. Countercurrent Chromatography: Apparatus, Theory and Applications; VCH Publishers: New York, 1990.
Conway, Walter D.; Petroski, Richard J. Modern Countercurrent Chromatography (ACS Symposium Series #593); ACS Publications, 1995.
Craig, Lyman C.; Post, Otto. Apparatus for countercurrent distribution. Anal. Chem. 1949, 21, 500-504.
Foucault, Alain P., Ed. Centrifugal Partition Chromatography (Chromatographic Science Series, Vol. 68); Marcel Dekker, Inc.: New York, 1995.
Ito, Y; Bowman, R L. Countercurrent chromatography: liquid-liquid partition chromatography without solid support. Science 1970, 167, 281-283.
Ito, Yoichiro. Golden rules and pitfalls in selecting optimum conditions for high-speed counter-current chromatography. Journal of Chromatography, A 2005, 1065, 145-168.
Ito, Yoichiro; Conway, Walter D., Eds. High-speed Countercurrent Chromatography (Chemical Analysis, Vol 132); John Wiley and Sons: New York, 1996.
Mandava, N. Bhushan; Ito, Yoichiro, Eds. Countercurrent Chromatography: Theory and Practice (Chromatographic Science Series, Vol. 44); Marcel Dekker, Inc.: New York, 1988.
Martin, A. J. P.; Synge, R. L. M. A new form of chromatogram employing two liquid phases. I. A theory of chromatography. II. Application to the microdetermination of the higher monoamino acids in proteins. Biochemical Journal 1941, 35, 1358-1368.
Menet, Jean-Michel; Thiebaut, Didier, Eds. Countercurrent Chromatography (Chromatographic Science Series Vol 82); Marcel Dekker, Inc.: New York, 1999.
Synge, R. L. M. Partition chromatography. Analyst 1946, 71, 256-258.
Tanimura, Takenori; Pisano, John J.; Ito, Yoichiro; Bowman, Robert L. Droplet countercurrent chromatography. Science 1970, 169, 54-56.