The basics in Centrifugal Partition Chromatography

Chromatography is a family of techniques for separating molecules according to their affinity for a stationary phase and a mobile phase. Among chromatographic techniques, centrifugal partition chromatography is distinguished by the liquid nature of the stationary phase. A relatively little-known technique, in the shadow of the major techniques such as gas chromatography and liquid chromatography, both of which use solid stationary phases, centrifugal partition chromatography sees in the absence of a solid support many advantages, but also specific features to be taken into account.

The principle of solute separation in centrifugal partition chromatography is extremely simple. At its heart is a system of two immiscible liquids. One of the liquid phases is kept stationary by a centrifugal field, while the second, mobile phase is pumped through the column. The solutes of interest injected at the top of the column will both migrate through the column, carried along by the mobile phase, and be distributed along the column between the two liquid phases, according to their partition coefficients. The selectivity of the column with regard to solutes is linked to the different partition coefficients of these solutes between the two immiscible phases.

It is important to note that the biphasic column requires specific centrifugal technology to maintain a stationary liquid phase. On the other hand, the instrumentation at the periphery of the column is common to all liquid chromatographic techniques, i.e. a pumping system and injector upstream, and a detector and/or collector downstream. The various technological options are described in this article.

The liquid nature of the stationary phase offers the user original modes of use and an unprecedented choice of column, leading to highly relevant selectivity of the technique to the target molecule(s). While these advantages have been exploited in the field of natural products, they have yet to be fully appreciated in other fields where separation is a crucial step.

By outlining the principles behind centrifugal chromatography and providing an overview of its applications, this article provides a basis for understanding the technique and its complementarity within the current range of separative techniques.