Ask the Editor: Centrifugal Partition Chromatography

An LCGC reader recently submitted the following question:

What is centrifugal partition chromatography, and what are its main applications?

Briefly, in centrifugal partition chromatography (CPC) one liquid acts as the stationary phase and a second solvent, containing the analytes, passes through it. Separation is achieved by partition of the solute between the two immiscible solvents comprising the mobile and stationary phases. CPC instruments share some of the components of liquid chromatography systems, including pumps, injection valves, and detectors, but the separation is completed in a rotor containing multiple coils or channeled disks rather than in a column containing a solid stationary phase. The liquid stationary phase is held in place by spinning rotor’s centrifugal field and the mobile phase is pumped through. The partitioning of the analytes with the stationary and mobile phases effects the separation. Wanasundara and Fedec (1) provide a good description of CPC in an article that discusses lipid separations using the technique. They call it “a liquid–liquid chromatography with a sorbent, requiring two immiscible solvent phases.”

According to a recent press release from ChromSolutions (Hemel Hempstead, UK), “The affinity of the solute for each phase, measured by their partition coefficient, determines the order of elution. In CPC there are no columns to replace or silica to recycle and solvent consumption is low, which means operating costs for preparative and industrial scale systems can be significantly reduced. Since separation and purification is not based on interactions with a silica support, some potential harmful interactions between valuable and desired isolates and silica are avoided. Sample losses due to irreversible binding and denaturation are also eliminated thus enhancing yield and overall purity. The solvent system in CPC can also be changed very quickly to suit a wide and diverse range of sample types from the purification of petroleum products to peptides. The system is also a true moving bed one with continuous injection if required. Preparative purification can be carried out from low gram to kilogram scales. CPC technology has been accepted and adopted by the pharmaceutical, nutraceuticals, cosmetics, and petroleum industries. Applications are diverse and include purification of natural substances, essential oils, chlorophylls, lipids, antibiotics from fermentation broths, and polyphenols. With regard to biotechnology CPC systems are ideal for the purification of peptides, proteins, and monoclonal antibodies.”

(1) U. Wanasundara and P. Fedec, Food Technology 13, 726–730 (Sept 2002); http://www.pos.ca/common/pdf/publications/cpc.pdf.

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